Rutile and its applications in earth sciences · · 2010-08-13Rutile and its applications in...

Earth-Science Reviews 102 (2010) 1–28

Contents lists available at ScienceDirect

Earth-Science Reviews

j ourna l homepage: www.e lsev ie r.com/ locate /earsc i rev

Rutile and its applications in earth sciences

Guido MeinholdCASP, University of Cambridge, West Building, 181a Huntingdon Road, Cambridge CB3 0DH, UK

E-mail address: [email protected].

0012-8252/$ – see front matter © 2010 Elsevier B.V. Aldoi:10.1016/j.earscirev.2010.06.001

a b s t r a c t
a r t i c l e i n f o
Article history:Received 5 August 2009Accepted 7 June 2010Available online 12 June 2010

Keywords:rutilemineral geochemistrygeothermometryoxygen isotopesgeochronologythermochronologyLu–Hf isotopes

Rutile is the most common naturally occurring titanium dioxide polymorph and is widely distributed as anaccessory mineral in metamorphic rocks ranging from greenschist to eclogite and granulite facies but is alsopresent in igneous rocks, mantle xenoliths, lunar rocks and meteorites. It is one of the most stable heavyminerals in the sedimentary cycle, widespread both in ancient and modern clastic sediments.Rutile has a wide range of applications in earth sciences. It is a major host mineral for Nb, Ta and other highfield strength elements, which are widely used as a monitor of geochemical processes in the Earth's crust andmantle. Great interest has focused recently on rutile geochemistry because rutile varies not only by bulkcomposition reflected, for instance, in its Cr and Nb contents but also by the temperature of crystallisation,expressed in the Zr content incorporated into the rutile lattice during crystallisation. Rutile geochemistry andZr-in-rutile thermometry yield diagnostic data on the lithology and metamorphic facies of sediment sourceareas even in highly modified sandstones that may have lost significant amounts of provenance information.Rutile may therefore serve as a key mineral in sediment provenance analysis in the future, similar to zircon,which has been widely applied in recent decades. Importantly, rutile from high-grade metamorphic rockscan contain sufficient uranium to allow U–Pb geochronology and (U–Th)/He thermochronology.Furthermore, in situ Lu–Hf isotope analysis of rutile permits insights into the evolution of the Earth's crustand mantle. Besides that, rutile is also of great economic importance because it is one of the favoured naturalminerals used in the manufacture of white titanium dioxide pigment, which is a major constituent in variousproducts of our daily life. Heavy mineral sands containing a significant percentage of rutile are therefore thefocus of exploration worldwide.This paper aims to provide an overview of the applications of rutile in earth sciences, based on a review ofdata published in recent years. After giving a summary of various rutile-bearing lithologies, the focus lies onrutile geochemistry, Zr-in-rutile thermometry, O isotope analysis, U–Pb geochronology, (U–Th)/Hethermochronology and Lu–Hf isotope analysis. A final outline of the economic importance of rutilehighlights the demand for further rutile-related research in earth sciences.

l rights reserved.

© 2010 Elsevier B.V. All rights reserved.

Contents

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22. Physical properties and geochemical composition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

2.1. General description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32.2. Crystal structure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42.3. Crystal chemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5

3. Occurrences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63.1. Rutile in metamorphic rocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 63.2. Rutile in igneous rocks and mineralisation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 83.3. Rutile in sedimentary rocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 93.4. Rutile in extraterrestrial rocks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

4. Applications of rutile in earth sciences . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104.1. Rutile geochemistry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

4.1.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104.1.2. Fe content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 104.1.3. Nb and Ta contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

http://dx.doi.org/10.1016/j.earscirev.2010.06.001

mailto:[email protected]

Unlabelled image

http://dx.doi.org/10.1016/j.earscirev.2010.06.001

Unlabelled image

http://www.sciencedirect.com/science/journal/00128252

2 G. Meinhold / Earth-Science Reviews 102 (2010) 1–28

4.1.4. Cr and Nb contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114.1.5. Other trace elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114.1.6. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

4.2. Zr-in-rutile thermometry . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134.2.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 134.2.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 144.2.3. Zr diffusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

4.3. Oxygen isotopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154.3.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 154.3.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

4.4. U–Pb geochronology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164.4.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164.4.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 174.4.3. Pb diffusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

4.5. (U–Th)/He thermochronology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194.5.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194.5.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

4.6. Lu–Hf isotopes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204.6.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204.6.2. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21

5. Economic importance of rutile. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215.1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 215.2. Economic importance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

6. Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

1. Introduction

With an estimated TiO2 concentration of about 0.7 wt.% (Rudnickand Fountain, 1995), titanium is theninthmost abundant elementof theEarth's continental crust. The most important titanium minerals arerutile (TiO2), ilmenite (FeTiO3) and titanite (CaTiSiO5) (Figs. 1 and 2).Rutile is an accessory mineral in a variety of metamorphic and igneousrocks and occurs as a detrital mineral in clastic sediments. Although themain formula of rutile is TiO2, there are commonly several possiblesubstitutions for titanium, for example, Al, V, Cr, Fe, Zr, Nb, Sn, Sb, Hf, Ta,W and U (e.g. Graham and Morris, 1973; Hassan, 1994; Fett, 1995;Murad et al., 1995; Smith and Perseil, 1997; Rice et al., 1998; Zack et al.,2002; Bromiley and Hilairet, 2005; Scott, 2005; Carruzzo et al., 2006).Variations in the geochemical composition are host rock specific andallow the rutile source to be traced and the chemical and physicalproperties during rutile formation to be characterised.

Great interest has focused on rutile geochemistry, because rutile isa major host mineral for high field strength elements (HFSE), amongstothers Nb and Ta, which are widely used as geochemical fingerprintsof geological processes such as magma evolution and subduction-zone metamorphism (e.g. Foley et al., 2000; Rudnick et al., 2000). Formany years, the significance of Nb and Ta concentrations and Nb/Tavalues of crustal and mantle rocks and the Earth's hidden suprachon-dritic Nb/Ta reservoir have been the subject of a lively debate (e.g.Green, 1995; Foley et al., 2000; Rudnick et al., 2000; Kalfoun et al.,2002; Zack et al., 2002; Xiao et al., 2006; Miller et al., 2007; Aulbach etal., 2008; Baier et al., 2008; Bromiley and Redfern, 2008; Schmidt etal., 2009).

Besides that, the Cr and Nb contents of rutile allow discriminationbetween various rutile source lithologies such as metapelitic rocks(e.g. mica-schists, paragneisses and felsic granulites) and metamaficrocks (e.g. eclogites and mafic granulites) (Zack et al., 2004b; Trieboldet al., 2007; Meinhold et al., 2008). Furthermore, the incorporation ofZr into the rutile crystal lattice has a strong dependence ontemperature and pressure, which has allowed the development ofZr-in-rutile geothermometers (Zack et al., 2004a; Watson et al., 2006;Tomkins et al., 2007). Several studies have already shown that Zr-in-rutile thermometry is an attractive method to calculate temperaturesof high-grade and ultrahigh-grade metamorphic rocks (e.g. Spear et

al., 2006; Zack and Luvizotto, 2006; Baldwin and Brown, 2008;Luvizotto and Zack, 2009). Moreover, rutile geochemistry combinedwith Zr-in-rutile thermometry can help to constrain the sedimentprovenance and has therefore already been applied successfully tosedimentary strata from the Precambrian to the Holocene worldwide(e.g. Zack et al., 2004b; Stendal et al., 2006; Triebold et al., 2007;Meinhold et al., 2008; Morton and Chenery, 2009).

Rocks exposed on the Earth's surface are prone to weathering anderosion. These processes have continuously modified the Earth'ssurface for probably more than 3.9 billion years producing clasticsediments. Some of the key pieces of evidence for that may recorddetrital zircons as old as 4.4 Ga from metaquartzites and metaconglo-merates of the Yilgarn Craton, Western Australia (Mojzsis et al., 2001;Wilde et al., 2001). Clastic sediments are composed of variousminerals(e.g. quartz, feldspar and mica) and lithic fragments and additionallycontain aminor amount of heavyminerals. The sediment compositionis primarily affected by the mineralogy of the primary source rock andby a complex set of parameters such as weathering, transport,deposition and diagenesis that modify the sediment during thesedimentary cycle (e.g. Morton, 1985; Morton and Hallsworth, 1999).

Besides whole-rock petrography and heavy-mineral analysis,geochemical studies of whole rock and specific detrital minerals arepowerful tools in provenance characterisation. Understanding clasticsediment provenance is important for exploration of mineralresources, basin analysis and palaeotectonic reconstructions. Themost common heavy minerals such as zircon, tourmaline, garnet andchrome spinel have long been used as provenance indicators by virtueof their geochemical and isotope signatures (e.g. Morton, 1991; vonEynatten and Gaupp, 1999; Morton et al., 2004, 2005; Mange andMorton, 2007). The exception is rutile, which received only minorattention until 2002 (Götze, 1996; Preston et al., 1998, 2002).However, rutile geochemistry, geothermometry and geochronologyyield diagnostic data on source-rock lithology andmetamorphic facieseven in highly modified sandstones that may have lost significantamounts of provenance information. Rutile may therefore serve as akey mineral in sediment provenance analysis in the future, similar tozircon, which has been widely applied in recent decades.

Studying the geochemical and physical parameters of rutile is notonly of scientific value. Rutile is an economically important mineral

Fig. 1. Transmitted light photomicrographs showing rutile crystals (a) in eclogite fromthe Cabo Ortegal complex, NW Spain (Harker Collection no. 146227) and (b) in maficgranulite from the Saxonian Granulite Massif, Germany (Harker Collection no. 26002).© 2009. Sedgwick Museum of Earth Sciences, University of Cambridge. Thephotomicrographs were taken by the author and are reproduced with permission.Mineral abbreviations (Kretz, 1983) are as follows: Cpx — clinopyroxene, Grt — garnet,Rt — rutile, and Zo — zoisite.

Fig. 2. Theoretical TiO2 content in various Fe–Ti oxide phases (modified from Reynekeand Wallmach, 2007). Titanite, a calcium titanium silicate, is shown for comparison.

3G. Meinhold / Earth-Science Reviews 102 (2010) 1–28

because of its use in the manufacture of white titanium dioxidepigment (Stanaway, 1994; Korneliussen et al., 2000), which is acomponent in products of our daily life such as paint, paper, plastics,toothpaste and sunscreen cream (Pearson, 1999; Carp et al., 2004;Gambogi, 2008). Mineral sands containing large percentages of rutileare therefore a focus of exploration worldwide (e.g. Goldsmith andForce, 1978; Force, 1991; Pirkle et al., 2007; Schlüter, 2008).

Recently, the search for secondary standards of natural rutile toassess measurement methods and demonstrate the quality ofacquired geochemical data (Luvizotto et al., 2009b) has also been afocus of scientific study. Hence, the scope of this paper is to provide anoverview of the applications of rutile in earth sciences, introducedwith an outline of the physical properties and geochemical compo-sition of rutile and a brief overview of various source lithologies forrutile. The latter part is relative brief because Force (1991) alreadygave a comprehensive overview of specific rutile sources, except forextraterrestrial material.

The current paper has the following structure: Section 1 states theobjectives of this work; Section 2 presents a review of the physicalproperties and geochemical composition of natural rutile and otherTiO2 polymorphs; Section 3 provides an overview of possible sourcelithologies including metamorphic rocks, igneous rocks, mineralisa-tion, sedimentary rocks and extraterrestrial rocks; Section 4 discussesthe applications of rutile geochemistry and Zr-in-rutile thermometry.

Both methods are evaluated in unravelling specific source character-istics and in use as a chemostratigraphic indicator. Furthermore,oxygen isotope analysis using the quartz–rutile mineral pair isdiscussed. In the past, powerful new analytical methods such as insitu U–Pb and Hf isotope analyses have been developed, whichsignificantly contribute to unravelling the geological history of naturalrutile and its host lithologies and are therefore addressed here too.Finally, Section 5 summarises the economic importance of rutile andshows the need for further rutile-related scientific research.

2. Physical properties and geochemical composition

2.1. General description

Abraham Gottlob Werner created the name rutile (Ludwig, 1803),which he assigned to a mineral originally known as “red schorl”. Thefirst description of “red schorl” is commonly attributed to Romé del'Isle (1783); however, von Born (1772), as pointed out by Papp(2007), already mentioned “red schorl” a few years earlier. Klaproth(1795) used “red schorl” (rutile) for the description of the elementtitanium, which he named after the Titans of Greek mythology. Notethat William Gregor originally discovered titanium (which he namedmenackanite) in ilmenite in 1791 (Trengove, 1972).

Although it has long been thought that Horcajuelo (also calledCajuelo) in the province of Burgos in Spain is the type locality of rutile,a thorough study by Papp (2007) has recently revealed that the typelocality of rutile is Revúca in Slovakia.

The name “rutile” is derived from the Latin rutilus because of thedeep red colour observed in some specimens in transmitted light.Rutile can be translucent or opaque. Yellowish and brownish coloursare also very common. A rarity is natural rutile with blue colour,which has only been described so far as needle-like inclusions ingarnet from ultrahigh-pressure metasedimentary rocks of the GreekRhodope Massif (Mposkos and Kostopoulos, 2001). In reflected lightrutile with bluish colour has been reported from several meteorites(El Goresy, 1971). The blue colour of meteoritic rutile may be due to astoichiometric deficiency of oxygen in the rutile structure (El Goresy,1971). Experiments on synthetic rutile have shown that blue coloursoccur in rutile samples grown or annealed under reducing conditions(Bromiley and Hilairet, 2005). Khomenko et al. (1998) demonstratedthat the colour of blue rutile is mainly due to intervalence charge

image of Fig.�1

image of Fig.�2

Fig. 3. Ternary system FeO–Fe2O3–TiO2 showing the major high-temperature solid-solution series magnetite–ulvöspinel, haematite–ilmenite, pseudobrookite–ferropseu-dobrookite (modified from Buddington and Lindsley, 1964). Phases were plotted onmole percentage basis.

Fig. 4. Structure of rutile (after Baur, 2007) approximately parallel [100], rotated by 4°around [001] and 8° around [010]. (a) Perspective view; one unit cell. (b) Perspectivepolyhedral view; three unit cells in [001] direction, corner sharing between twooctahedral rutile type chains.


transfer between Ti3+ and Ti4+ ions on adjacent interstitial andoctahedral sites (see Bromiley and Hilairet, 2005).

Rutile has a density of 4.23 g cm−3, but can range up to 5.50 g cm−3

(Deer et al., 1992), and thus belongs to the heavy mineral suite, whicharemineralswith density N2.8 g cm−3. Rutile is commonly diamagnetic(non-magnetic), and therefore, it can easily be separated from theparamagnetic (weakly magnetic) and ferromagnetic (strongly magnet-ic) heavymineral fraction using the Frantz isodynamic separator (Buist,1963a). However, rutile can also contain a high proportion of Femakingit magnetic, and hence it could remain in the magnetic heavy mineralfraction (Buist, 1963a; Hassan, 1994). Bramdeo and Dunlevey (2000)mentioned anomalousbehaviourof detrital rutile (due to substitution ofcations other than Ti4+ in the rutile crystal lattice; Fig. 8) duringindustrial magnetic and electrostatic mineral separation, which cancause rutile loss. Recent studies show that Co-implanted rutile canbecome ferromagnetic (Akdogan et al., 2006). Themelting point of purerutile is around 1825–1830 °C (MacChesney and Muan, 1959; Deeret al., 1992). Note that synthetic rutile can be produced by heating asolution of TiCl4 to 950 °C or by heating anatase to above 730 °C (Deeret al., 1992).

2.2. Crystal structure

In nature, titanium dioxide mainly occurs in three structuralstates: rutile, anatase and brookite (Fig. 2). Together they form theTiO2 end-member of the ternary system FeO–Fe2O3–TiO2 (Fig. 3).

Table 1Physical parameters of selected TiO2 polymorphs.

Rutile Anatase Brookite Ti

Density (g cm−3) 4.23–5.5 3.82–3.97 4.08–4.18 3.Crystal system Tetragonal Tetragonal Orthorhombic MSpace group P42/mnm I41/amd Pbca C2Unit cell parameters (Å) a=4.594

c=2.959a=3.785c=9.514

a=9.184b=5.447c=5.145

a=b=c=β

Comment VOReference (1) (2) (3) (4

References: (1) Cromer and Herrington (1955), Baur (1956), Deer et al. (1992); (2) Cromer aal. (1992); (4) Marchand et al. (1980); (5) Simons and Dachille (1967), Hwang et al. (2000

Rutile crystallises in the tetragonal space group P42/mnm and is themost common phase, with unit cell parameters a=4.594 Å andc=2.959 Å for pure rutile (Baur, 1956) (Table 1). Natural rutile,however, commonly contains various trace elements such as Nb, Vand Fe, as outlined in Section 2.3, and hence has distinctly higher unitcell parameters (e.g. Černý et al., 1999). The structure of pure rutile isshown schematically in Fig. 4. In the unit cell, each Ti4+ ion issurrounded by six oxygens at the corners of a slightly distorted,regular octahedron while each oxygen surrounded by three Ti4+ ionsis lying in a plane at the corners of an approximately equilateraltriangle (Deer et al., 1992; Baur, 2007). Baur (2007) gives a moredetailed crystallographic description.

Rutile is a high-pressure and high-temperature polymorph and isisostructural with stishovite, a high-pressure silica polymorph (Fig. 5).Stishovite is a major phase in subducting oceanic crust under lowermantle conditions (Ono et al., 2001) and has also been described fromimpact-related rocks (Chao et al., 1962) and meteorites (Sharp et al.,1999). The behaviour of rutile at high and ultrahigh pressurestherefore offers an analogy to explore post-stishovite phase transitions(El Goresy et al., 2001; Bromiley et al., 2004). The low-temperaturepolymorphs of titanium dioxide are anatase (tetragonal) and brookite(orthorhombic). Under relatively low temperatures and pressures,rutile is metastable with respect to anatase when the TiO2 crystal sizeis less than ∼14 nm, because the surface energy of rutile is then muchhigher than that of anatase (see Smith et al., 2009 for discussion).

Besides rutile, anatase and brookite, there are at least threeadditional TiO2 polymorphs (Table 1). The TiO2(B) polymorph has astructure closely related to that of VO2(B) (Marchand et al., 1980), theTiO2(II) polymorph has an α-PbO2-type structure (Simons and

O2(B) TiO2(II) TiO2(H)

64 4.33 3.46onoclinic Orthorhombic Tetragonal/m Pbcn I4/m12.163.746.51

=107.29°

a=4.59b=5.44c=4.94

a=10.18c=2.97

2(B)-related structure α-PbO2-type structure Hollandite-type structure) (5) (6)

nd Herrington (1955), Deer et al. (1992); Howard et al. (1991); (3) Baur (1961), Deer et); (6) Latroche et al. (1989).

image of Fig.�3

image of Fig.�4

Fig. 5. Pressure–temperature diagram (after Okamoto andMaruyama, 2004; Baldwin etal., 2004). Phase boundaries for rutile and TiO2(II) are based on phase equilibriumexperiments, nominally dry synthesis experiments and reference data (after Withers etal., 2003). A range of geotherms is also shown. Abbreviations: GS, greenschist facies;AM, amphibolite facies; GR, granulite facies; BS, blueschist facies; EC, epidote facies.

Fig. 6. Raman spectra of the TiO2 polymorphs rutile, anatase and brookite.Wavenumbers of main Raman bands are indicated (see text for explanation).


Dachille, 1967) and the highly metastable TiO2(H) polymorph has ahollandite-type structure (Latroche et al., 1989). For several decades,the last two were only known from synthetic polymorphs. However,Hwang et al. (2000) described an epitaxial (about 8 nm thick) slab ofthe TiO2(II) polymorph between twinned rutile bicrystals as inclusionin garnet of diamondiferous quartzofeldspathic rocks from theSaxonian Erzgebirge, Germany, which was the first natural TiO2(II)polymorph found on Earth. This occurrence was explained by Hwanget al. (2000) to have formed during ultrahigh-pressure progrademetamorphism close to the rutile–α-PbO2 phase boundary in thediamond stability field at depths of at least 130 km. The rockscontaining this TiO2(II) polymorph may have equilibrated at pres-sures in excess of 70 kbar (Withers et al., 2003) (Fig. 5). Anothernatural TiO2(II) polymorph was reported in omphacite from a coesite-bearing eclogite in the Dabie Mountains, China (Wu et al., 2005). Wuet al. (2005) suggested subduction of continental material to depths ofover 200 km. El Goresy et al. (2001) discovered a natural shock-induced TiO2(II) polymorph from shocked garnet–cordierite–silli-manite gneiss clasts of the Ries crater, Germany. Its petrographicsetting is entirely different from that of the epitaxial slab in theSaxonian diamondiferous gneisses (see description in El Goresy et al.,2001 for further details). Another natural shock-induced TiO2(II)polymorph has been identified in breccias from the Chesapeake Bayimpact structure in Virginia, U.S.A. (Jackson et al., 2006).

Because the mineral polymorphs of TiO2 cannot be distinguishedby their geochemical composition other identification methods suchas X-ray diffraction (Spurr and Myers, 1957; Raman and Jackson,

1965) and reflected light microscopy (Mader, 1980) have to be used.The most reliable technique to identify mineral polymorphs is lasermicro-Raman spectroscopy. A compilation of Raman bands for thethree major structural TiO2 polymorphs is shown in Fig. 6. Rutile canbe identified by bands at wavenumbers 143, 247, 447 and 612 cm−1

(Porto et al., 1967; Tompsett et al., 1995) and anatase by bands atwavenumbers 144, 197, 400, 516 and 640 cm−1 (Ohsaka et al., 1978).Brookite is characterised by several bands. Strong bands are atwavenumbers 153, 247, 322 and 636 cm−1 (Tompsett et al., 1995).

2.3. Crystal chemistry

Presently, analysis of rutile can be routinely performed bysophisticated techniques such as electron microprobe (EMP), protonmicroprobe (PIXE) and laser ablation inductively coupled plasmamassspectrometry (LA-ICP-MS) so that differences in geochemical compo-sition can easily be identified (Fig. 7). The disadvantage of the LA-ICP-MS technique is that it makes a crater often several tens ofmicrometres in diameter whereas the first two techniques arenondestructive to the sample, but they have higher detection limits(especially EMP) for the concentration of certain elements comparedwith LA-ICP-MS facilities. For very tiny rutile crystals analysed in thinsections, it is recommended that the Si content is measured in order toidentify beam interferences with adjacent silicate minerals (Carruzzoet al., 2006; Baldwin and Brown, 2008). Smith and Perseil (1997)considered Si substitution in rutile as “highly contentious at non-ultra-high pressure” and thus if Si is detected in rutile of non-ultrahigh-pressure rocks it is likely to be due to analytical error, microinclusions,or introduction into defective parts of the crystal structure (Smith andPerseil, 1997). Moreover, very fine zircon lamellae can occur in rutile(Schmitz and Bowring, 2003; Downes et al., 2007), which may cause

image of Fig.�5

image of Fig.�6

Fig. 8. Ionic charge versus ionic radius (Shannon, 1976) for elements that substitute Tiin natural rutile (see text for explanation and references). Note that the ionic radius ofTa5+ is about 0.015 Å smaller than that of Nb5+ (Tiepolo et al., 2000).


elevated Zr contents if such zircon lamellae-rich rutiles are analysed.Thus, rutile measurements with Si contents N300 ppm showingabnormally high Zr contents should be excluded from the data set(see Zack et al., 2004a; Luvizotto and Zack, 2009 for furtherdiscussion). Rutiles from diamondiferous kyanite-bearing eclogitescan contain elevated Al contents, which can be explained by severaltiny rods of corundum (Sobolev and Yefimova, 2000). Ilmenite andmagnetite may also occur as tiny lamellae in rutile. In general, if suchmineral rods are smaller than the electron beam size amixture of themand rutile is analysed. Literature data show a wide range of certaintrace elements, in particular Al and Fe, in rutile fromcrustal andmantleeclogites, which most likely reflects the presence of corundum andilmenite lamellae (Sobolev and Yefimova, 2000).

Most naturally occurring rutile corresponds to the general formulaTiO2, with titanium occurring as Ti4+. Note that titanium also exists indifferent states of oxidation: besides Ti4+, there are also Ti3+, Ti2+ andTi0 (MacChesney andMuan, 1959). In rutile, there are commonly severalpossible substitutions for titanium such as hexavalent (W6+ and U6+),pentavalent (Nb5+, Sb5+andTa5+), tetravalent (Zr4+,Mo4+, Sn4+,Hf4+

and U4+), trivalent (Al3+, Sc3+, V3+, Cr3+, Fe3+ and Y3+) and divalent(Fe2+, and to a lesser degree Mg2+, Mn2+ and Zn2+) cations (GrahamandMorris, 1973;Brenanet al., 1994;Hassan, 1994; Fett, 1995;Muradetal., 1995; Smith and Perseil, 1997; Rice et al., 1998; Zack et al., 2002;Bromiley and Hilairet, 2005; Scott, 2005; Carruzzo et al., 2006). Forinstance, Fe3+ and Nb5+ incorporation (Fe3++Nb5+↔2Ti4+) main-taining charge neutrality can compensate for substitution of tetravalentTi4+ ions. Several further examples can be found in the literature (e.g.Urban et al., 1992;Michailidis, 1997; Smith and Perseil, 1997; Rice et al.,1998; Scott and Radford, 2007). Substitution of Ti4+ in the rutile crystallattice is based on the ionic radius and ionic charge of the substitutedcation (Fig. 8). Cathodoluminescence (CL) and backscattered electron(BSE) images of polished rutile grains can reveal complex oscillatoryzonation patterns or patchy zoned crystals (e.g. Michailidis, 1997;Carruzzo et al., 2006; Birch et al., 2007), which indicate variations in thegeochemical composition in the rutile crystal lattice. Thus, a single-spot

Fig. 7. Comparison of Nb concentrations in rutiles analysed by EMP and LA-ICP-MS. Datawere taken from Zack et al. (2002) and Xiao et al. (2006). Dark grey diamonds arerutiles from eclogites, grey squares represent rutiles from quartz veins, and the whitecircles represent rutiles from garnet–mica schists. Solid line represents a 1:1correlation; dotted lines are the upper and lower range of 20% and 30% deviationsfrom the 1:1 line respectively. Note that EMP gives a slightly lower value compared toLA-ICP-MS for most of the analysed rutiles, also recognised by Xiao et al. (2006). Futurestudies may help clarifying if this is an analytical artefact.

analysis may not be representative for the bulk composition of a rutilegrain. That is particularly critical for calculating the crystallisationtemperatures using Zr-in-rutile thermometry and for in situ isotopeanalysis.

Rutile is the dominant carrier of HFSE (e.g. Foley et al., 2000; Kalfounet al., 2002; Zack et al., 2002). For example, in eclogites 1 modal-% ofrutile can carry more than 90% of the whole-rock content for Ti, Nb, Sb,Ta andWand considerable amounts (5–45% of thewhole-rock content)of V, Cr,Mo and Sn (Rudnick et al., 2000; Zacket al., 2002). Because rutiledominates the budget of Nb and Ta, Nb+Ta concentrations and Nb/Tavalues of rutile shouldbe identical to that of the host rock (Rudnick et al.,2000; Zack et al., 2002; Carruzzo et al., 2006). Schmidt et al. (2009)recently made a critical note on this subject, based on Nb/Ta zoning ineclogitic rutile. In general, the rutile structure can accommodate up to37 wt.%Nb2O2 in solid solution (Roth and Coughanour, 1955; Tien et al.,1969). Villaseca et al. (2007) suggested that around 10–35% of thewhole-rock Zr content of peraluminous granulites could be contained inrutile. The needle-like blue rutile inclusions in garnet from ultrahigh-pressuremetasedimentary rocks of the Greek RhodopeMassif contain asmall but significant amount of SiO2 (Mposkos and Kostopoulos, 2001)that indicates high-temperature/high-pressure (HT/HP) conditions andrepresents stishovite component in rutile (H.-J. Massonne, in Mposkosand Kostopoulos, 2001).

Rutile can also contain considerable amounts (tens to thousands ofppm) of H2O, structurally bounded as hydroxyl (OH), which has beenreported from both synthetic rutile (Bromiley et al., 2004; Bromileyand Hilairet, 2005) and natural rutile (Rossman and Smyth, 1990;Hammer and Beran, 1991; Vlassopoulos et al., 1993; Zhang et al.,2001). Vlassopoulos et al. (1993) pointed out that rutile is one of themost “hydrous” nominally anhydrous minerals (NAMs: Bell andRossman, 1992) so far identified. Experimental investigations haveshown that OH solubility in NAMs increases with pressure (e.g. Lu andKeppler, 1997; Bromiley et al., 2004; Mierdel and Keppler, 2004;Rauch and Keppler, 2004). Zhang et al. (2001) presented values ofabout 4300 to 9600 ppm H2O in rutile from eclogites of the DabieMountains, China. Therefore, besides pyroxene and garnet, rutile isalso an important NAM to recycle water into the mantle (Zhang et al.,2001; Zheng et al., 2003; Bromiley et al., 2004).

3. Occurrences

3.1. Rutile in metamorphic rocks

Rutile is mainly formed during medium- to high-grade metamor-phic processes (e.g. Goldsmith and Force, 1978; Force, 1980, 1991)(Fig. 9), but it can also form in low-grade metamorphic rocks (e.g.

image of Fig.�7

image of Fig.�8

Fig. 9. Illustrations showing the main stages of rutile crystallisation from ilmenite andbiotite during prograde metamorphism. (a) Rutile crystallisation from ilmenite in low-tomedium-grade metasedimentary rocks of the Erzgebirge (modified from Luvizotto etal., 2009a). (b) Rutile crystallisation from biotite in granulite facies paragneisses of theIvrea–Verbano Zone (modified from Luvizotto and Zack, 2009). Mineral abbreviations(Kretz, 1983) are as follows: Bt = Biotite, Chl = Chlorite, Ilm = Ilmenite, Rt = Rutile.

Fig. 10. Experimentally determined formation of rutile, titanite and ilmenite for a mid-ocean ridge basalt–H2O system (after Liou et al., 1998). The P–T field phase boundarieswere not reversed and hence should be considered as synthesis boundaries, althoughthey are topologically consistent with natural occurrences of Ti-phases. Liou et al.(1998) furthermore pointed out that these Ti-rich phases are not related to one anotherby simple polymorphic transition, and thus two or even three of them may coexistunder certain physicochemical conditions, but this was not investigatedexperimentally.


Banfield and Veblen, 1991; Luvizotto et al., 2009a). Rutile in low- tomedium-grade metamorphic rocks typically occurs as small (∼20–100 μm), scattered grains, generally needle-like crystals, or polycrys-talline aggregates. Banfield and Veblen (1991) recognised that withineach sample analysed, the rutile crystals are uniform in size, but theyare smaller in samples from the chlorite and chloritoid zones than insamples from the garnet and staurolite zones. The needle-like,euhedral morphology of the crystals show that rutile grew duringmetamorphism, rather than being detrital in origin (Banfield andVeblen, 1991). Luvizotto et al. (2009a) recently described prograderutile crystallisation in low- to medium-grade metasedimentary rocksfrom the Saxonian Erzgebirge, Germany. The rutiles form polycrys-talline aggregates made of fine-grained intergrowths of rutile andchlorite that replaces ilmenite (Fig. 9). Luvizotto et al. (2009a)suggested that rutile has been derived from ilmenite breakdown dueto following simplified reaction:

Ilmeniteþ Silicatesþ H2O→Rutile þ Chlorite

Rutile in high-grade and ultrahigh-grade metamorphic rocks (e.g.eclogites, granulites) forms mainly single crystals in the matrix butalso occurs as inclusion in other minerals such as garnet, pyroxene,amphibole and zircon (Fig. 1). These rutile grains can show euhedralto subhedral forms with oval shapes or irregular shapes, with grainsizes from a few μmup to a fewmm (Hills and Haggerty, 1989; Brenanet al., 1994; Zack et al., 2002; Huang et al., 2006; Xiao et al., 2006;Janoušek et al., 2007; Chen and Li, 2008). Brenan et al. (1994)described large (1–5 mm in size), euhedral single crystals of rutilethat contain fine exsolution lamellae of ilmenite from an eclogite vein

sample of the Rocciavre Massif, Western Alps. Smythe et al. (2008)noted that ilmenite lamellae are abundantly present in mantle-derived rutile.

Eclogite is the major rock type under high-grade metamorphicrocks containing large percentages of rutile (Korneliussen and Foslie,1985; Liou et al., 1998; Korneliussen et al., 2000; Zack et al., 2002;Chen et al., 2005; Huang et al., 2006; Zhang et al., 2006). Korneliussenand Foslie (1985) estimated that about 90% of the titanium ineclogites of the Sunnfjord region of the Western Gneiss Region(WGR), Norway, is hosted in rutile. Eclogite from the WesternLigurian Alps contains up to 4 vol.% of rutile (Liou et al., 1998). Eclogiteis a plagioclase-free metamorphic rock composed of ≥75 vol.% ofgarnet and Na-rich clinopyroxene (omphacite) and mainly forms bysubduction of gabbroic or basaltic rocks to great depths where rutilecrystallises from Fe–Ti oxides and Ti-bearing silicates during meta-morphic recrystallisation (Krogh, 1980, 1982; Korneliussen andFoslie, 1985; Liou et al., 1998; Korneliussen et al., 2000; Miller et al.,2007; Figs. 5 and 10). Eclogite has a density of up to 3.6 g cm−3 (Hillsand Haggerty, 1989; Rudnick and Fountain, 1995), higher than anyother crustal rock (Hacker, 1996), even peridotite, which it exceeds by0.2–0.4 g cm−3 (Rudnick and Fountain, 1995). Experimental datasuggest that rutile is the main Ti carrier in eclogite below 150 kbarunder sub-solidus conditions, even in relatively Ti-poor systems(Okamoto and Maruyama, 2004). However, under ultrahigh-pressuremetamorphic conditions close to the coesite–stishovite phase bound-ary it is more likely to be the TiO2(II) polymorph instead of rutile(Withers et al., 2003; Fig. 5). In general, the stability of rutile insubducted lithosphere is a complex function of whole-rock compo-sition, temperature and pressure (e.g. Zhang et al., 2003; Klemme etal., 2005; Bromiley and Redfern, 2008; Fig. 10).

Since rutile is a major accessory mineral in eclogite and plays amajor role in the Earth's HFSE budget (in particular Nb and Ta) (seeSection 2.3), in the last decade, eclogite has received much attentionregarding its whole-rock and mineral geochemical composition (e.g.Rudnick et al., 2000; Zack et al., 2002; Xiao et al., 2006; Miller et al.,2007; Schmidt et al., 2009). In addition, the processes returning

image of Fig.�9

image of Fig.�10


extremely dense eclogite from great depths back to the Earth's surface(e.g. Guillot et al., 2000; Neufeld et al., 2008), supplemented bygeochronological studies (e.g. Baldwin et al., 2004; Glodny et al.,2005; Kylander-Clark et al., 2008), have been much discussed.Unfortunately, the original mineral assemblage of lower crustalrocks such as eclogite and eclogite facies rocks are subject toretrogression during their ascent from great depths to the Earth'ssurface. For example, in eclogites and eclogite facies rocks from theWestern Ligurian Alps, rutile was subsequently replaced by ilmeniteand titanite along margins and cracks (Liou et al., 1998). Xiao et al.(2006) described thin titanite (10–20 μm) replacement surroundingrutile and a thin ilmenite (a few μm) rim at the rutile margin from aneclogite and nearby quartz vein, respectively, of the Dabie–Suluultrahigh-pressure terrane in east-central China. Note that, underconditions of rapid exhumation (as fast as subduction; Rubatto andHermann, 2001; Baldwin et al., 2004) the original mineral assemblageis largely preserved and allows insights into the pressure, temperatureand geochemical conditions present at great depths. Rutile in eclogitic(E-type) diamonds and diamondiferous eclogites (Prinz et al., 1975;Mvuemba Ntanda et al., 1982; Sobolev et al., 1997; Sobolev andYefimova, 2000) are accessible at the Earth's surface due to fast ascentfrom the Earth's mantle as xenoliths in kimberlite pipes. The extensivestudies of the composition of eclogite in recent years have sig-nificantly contributed to the increase of geochemical data for naturalrutile, and thus they have opened newways for rutile characterisationsuch as rutile geochemistry and Zr-in-rutile thermometry, as outlinedin Section 4.

Rutile also occurs in the form of oriented, needle-like rods, knownas sagenitic texture. Shau et al. (1991) described these from matrixbiotite of an orthogneiss of the Tananao metamorphic complex, NETaiwan. Van Roermund et al. (2000) described oriented, needle-likerutile rods of 2–15 μm in diameter and up to 200–300 μm in lengthfrom protogranular and porphyroclastic garnet from garnet peridotiteof theWGR. Attoh and Nude (2008) recently described spindle shapedrutile rods of b3 μm in diameter, b50 μm long and arranged in arectilinear pattern in garnet megacrystals frommafic granulites of thePan-African Dahomeyide suture zone, SE Ghana. Oriented, needle-likerutile rods in garnet are commonly taken as an indicator for UHPmetamorphism (Ye et al., 2000; Mposkos and Kostopoulos, 2001;Hwang et al., 2007; Attoh and Nude, 2008). They show crystallo-graphically controlled growth of the exsolution rods and suggesttransformation in the garnet crystal structure involving substitutionof Ti4+ in the precursor garnet structure (Zhang et al., 2003). Hwanget al. (2007) investigated the origin of oriented, needle-like rutile rodsin garnet from eclogitic rocks of Sulu, from diamondiferous quartzo-feldspathic rocks of the Saxonian Erzgebirge and from felsic granuliteof Bohemia. Their results argue against a simple solid-state precip-itation scenario. The authors favour a mechanism where orientedrutile needles form by cleaving and healing of garnet with rutiledeposition because of the natural analogue of oriented titaniteneedles in biotite. Nonetheless, their study clearly shows the needfor further investigation of the origin of oriented rutile needles ingarnet of high-grade and ultrahigh-grade metamorphic rocks (seeGriffin, 2008).

3.2. Rutile in igneous rocks and mineralisation

Additional sources of rutile can be quartz veins (e.g. Watson, 1922;Deer et al., 1992), granites (e.g. Force, 1980; Scott, 1988; Force, 1991;Michailidis, 1997; von Quadt et al., 2005), pegmatites (e.g. Force,1980; Černý et al., 1989; Force, 1991; Deer et al., 1992; Okrusch et al.,2003), carbonatites (e.g. Bailey, 1961; Ripp et al., 2006; Doroshkevichet al., 2007), kimberlites and xenoliths of metasomatised peridotite(e.g. McGetchin and Silver, 1970; Dawson and Smith, 1977; Joneset al., 1982; Kramers et al., 1983; Tollo and Haggerty, 1987; Schulze,1990; Rudnick et al., 2000; Grégoire et al., 2002; Kalfoun et al., 2002;

Choukroun et al., 2005; Downes et al., 2007; Smythe et al., 2008) andmetallic ore deposits (e.g. Bayley, 1923; Force, 1980; Czamanske et al.,1981; Force, 1991; Rice et al., 1998; Clark and Williams-Jones, 2004;Scott, 2005; von Quadt et al., 2005; Scott and Radford, 2007). Theoccurrence of large rutile crystals (up to 4 cm in size and larger) islimited to some granitic pegmatites and vein mineralisation (Watson,1922; Deer et al., 1992; Černý et al., 1999, 2007) and are describedfrom syn-metamorphic quartz veins of eclogite facies (Franz et al.,2001; Gao et al., 2007).

In alpine fissures, rutile can occur as reddish needles in transparentquartz crystals. They are then called rutilated quartz or “fléchesd'amour” (“arrows of love”) and are classified as gemstones, withknown localities in Brazil, Switzerland and U.S.A. (Pough, 1998).

Blue quartz is another type of rutilated quartz (e.g. Wise, 1981).The “blue” colour of quartz is derived from Rayleigh scattering of lightby abundant inclusions of nanometre-scale acicular rutile, but otherminerals may also occur as inclusions, for instance, ilmenite (e.g.Wise, 1981; Zolensky et al., 1988). In many cases, acicular rutile inquartz has been formed by exsolution of Ti from the quartz crystallattice (Cherniak et al., 2007a). Rutilated blue quartz has beendescribed, for example, from granites, granodiorites, rhyolites,charnockites and gneisses (Wise, 1981; Zolensky et al., 1988, andreferences therein), and is restricted in occurrence mainly to thePrecambrian, in particularly to middle to late Proterozoic rocks(Zolensky et al., 1988) of the Grenville province. Note that blue quartzincorporated into detritus eroded from these rocks has proven to be areliable provenance indicator with stratigraphic significance both inthe Scottish Highlands, in western Ireland and in the eastern parts ofNorth America (Phillips, 1973; Fitches et al., 1990; Kline, 1991; Deweyand Mange, 1999; Maria Mange, pers. comm., 2010).

Rutile in granitic rocks can have several origins; it can be a primaryigneous, peritectic, xenocrystic, or secondary phase (Carruzzo et al.,2006; Clarke and Carruzzo, 2007). Secondary rutile can form becauseof hydrothermal alteration (chloritisation) of Ti-rich biotite (Carruzzoet al., 2006), by oxidation of ilmenite (Sakoma andMartin, 2002) or byexsolution from Ti-bearing phases such as clinopyroxene and garnet(Zhang et al., 2003).

Primary igneous rutile can have significant concentrations of HFSE(e.g. Nb and Ta). Niobian rutile (also known as ilmenorutile) is avariety of rutile with an atomic ratio of Nb/TaN1, while tantalian rutile(also known as strüvertite) has an atomic ratio of Nb/Tab1 (Černý etal., 1964). Both are accessory minerals in peraluminous to peralkalinegranites and substantial components of hydrothermal assemblagesassociated with alkaline intrusive rocks (Černý et al., 1964, 1999;Černý and Chapman, 2001). In both rutile varieties, Fe3+ is alwayspresent to accommodate the overcharged (Ti4+, Nb5+ and Ta5+)cation population (Smith and Perseil, 1997).

According to Bailey (1961) and Marvin (1971), in alkaline rocks,carbonatites and carbonate veins in particular, rutile tends to beenriched in Nb and poor in Ta. However, primary rutiles fromcarbonatites can be free of Nb, and have ubiquitous V and elevated Fecontents (Ripp et al., 2006). Chrome-rich rutile in carbonatites iscommonly related to mantle-derived xenoliths (Ripp et al., 2006).Anderson (1960) mentioned niobian rutile from the carbonate-richmetamorphic zone of the Idaho batholith. Tollo and Haggerty (1987)described niobian rutile from nodules of the Orapa kimberlite,Botswana. Kimberlitic rutile in general has higher Nb/Ta ratioscompared with rutile from granites and granitic pegmatites (Tollo andHaggerty, 1987). Metasomatised mantle peridotite and continentallithospheric mantle have Nb/Ta ratios N17.5, chondritic to suprachon-dritic (Kalfoun et al., 2002). Unmetasomatised peridotites commonlyhave Nb/Ta ratios b17.5, subchondritic (Kalfoun et al., 2002).

Michailidis (1997) studied niobian rutile (some with substantialtungsten content) from theFanos aplitic granite, northernGreece.Černýet al. (1999) described niobian rutile from the McGuire pegmatite,Colorado, and its breakdown into secondary minerals such as


pseudobrookite, ferropseudobrookite, titanian ferrocolumbite andilmenite. Further examples of exsolution and breakdown of niobianrutile are found in the literature (Uher et al., 1998; Černý and Chapman,2001; Černý et al., 2007). Carruzzo et al. (2006) described several rutiletypes from peraluminous granite of the late Devonian South MountainBatholith, Nova Scotia. The size of the primary igneous rutilegrains ranges from 0.04 to 0.28 mm (with minor larger grains),with rare euhedral to commonly anhedral shapes. Carruzzo et al.(2006) recognised that these grains have increasing concentrations ofFe+Mn, Zr, Nb, Sn, Ta andWwith increasing chemical differentiation ofthe South Mountain Batholith and concluded that rutile is a sensitivemonitor of Nb–Ta–Sn–W in the batholith. Rutile with high Nb+Taconcentrations and low Nb/Ta values, reflecting variable partitioning ofNb and Ta into a fluid phase, is commonly associated with graniticpegmatites and in case of the South Mountain Batholith may representcrystallisation during H2O-oversaturated conditions (Carruzzo et al.,2006).

Concentrations of boron and H2O can increase in granite magmasduring the late stage of emplacement and can led to explosive releaseof volatiles forming tourmaline breccia dykes and pipes, some ofwhich have rutile as the main accessory phase (e.g. Müller and Halls,2005). Such rutile has highly variable amounts of V, Fe, Nb, Sn and W(Müller and Halls, 2005). Putnis (1978) and Putnis andWilson (1978)noted that rutile formed at low temperatures (less than 450 °C,hydrothermal) contains notable Fe concentrations. Such rutile issusceptible to exsolution of a Fe-bearing phase such as hematite(Putnis, 1978; Putnis and Wilson, 1978).

3.3. Rutile in sedimentary rocks

The largest sedimentary sources of rutile are fine-grained clasticsediment and heavy mineral sands (placer deposits). For example,Valentine and Commeau (1990) studied the TiO2 whole-rock contentof Pleistocene and Holocene sediments from surficial and several coresamples of the Gulf of Maine where rutile is the main titanium sourcepresent in the silt and clay fraction. Based on their data, the authorsestimated the amount of TiO2 to exceed 647 millionmetric tons (t) andcould show that the Gulf of Maine hosts a large titanium resource.Placer deposits commonly contain high percentages of zircon, rutileand ilmenite that are concentrated to economic grade (e.g. Force,1991; Roy, 1999; Dill, 2007a). Examples are marine placer deposits insoutheastern Australia (e.g. Roy, 1999) and along the NW coast ofSouth Africa (e.g. Dill, 2007a; see Section 5). In continental placerdeposits, titaniumminerals occurmainly in rutile–ilmenite aggregatescalled “nigrine” (Clark, 1993; Dill, 2007a; Dill et al., 2007). Nigrine is avariety of rutile with high iron concentration (Clark, 1993).

Pseudorutile (Fe2Ti3O9; Temple, 1966; Teufer and Temple, 1966) isformed by Fe2+ removal during oxidation of ilmenite (FeTiO3) (Teuferand Temple, 1966; Grey and Reid, 1975; Mücke and Chaudhuri, 1991;Grey et al., 1994). Its status as a distinct mineral phase is still a subject oflively debate (Dill, 2007a, and references therein). Removal of Fe3+ frompseudorutile due to leaching and hydrolisation results in leucoxene(Mücke and Chaudhuri, 1991). The latter term, introduced by Gümbel(1874), had long been applied to alteration products with high Ticoncentration. In present usage, leucoxene refers to a mineralconcentrate with about 65–90 wt.% TiO2 (Fig. 2) and is a mixture ofpseudorutile and rutile (Grey et al., 1994; Reyneke andWallmach, 2007).In conclusion, pseudorutile and leucoxene indicate more oxidisingsupergene or hypogene conditions in the provenance area (Dill, 2007a).

In sedimentary rocks rutile, anatase and brookite can form dia-genetically from Ti-rich pore-solutions, which may derive fromalteration of ilmenite, titanite and biotite (Mader, 1980; Morad, 1986;Valentine and Commeau, 1990). Paine et al. (2005) ascribed alterationof ilmenite to pseudorutile and anatase in Pliocene placer depositsof southeastern Australia to postdepositional weathering. The TiO2

polymorphs are commonly alteration endmembers of Fe–Ti oxides

(ReynekeandWallmach, 2007).Authigenic rutile canoftenbe identifiedby its polysynthetic twin lamellae (Mader, 1980).

Rutile has been recognised as an important component of heavymineral suites since the very early days of sedimentary petrography(e.g. Boswell, 1933, and references therein). Hubert (1962) intro-duced the zircon–tourmaline–rutile (ZTR) index as a quantitativeindicator of the mineralogical maturity of the heavy mineral suite insandstones. Buist (1963a,b) determined the rutile concentration ofheavy mineral separations of beach sands from southern Australiausing a Frantz isodynamic separator and Geiger counter X-raydiffractometer. Raman and Jackson (1965) used X-ray diffractionafter sample treatment with hydrofluoric acid for the qualitativedetection and quantitative estimation of rutile in small amounts insediment. From the 1980s, microprobe techniques were used forsingle-grain chemical analyses supplying additional information toconventional heavy mineral analysis for sediment provenance studies(e.g. Morton, 1985, 1991). This caused a resurgence of interest inheavy mineral analysis both in academic research and in industry.

Rutile is chemically and physically stable and not prone todestruction during the sedimentation cycle and can therefore provideimportant information about source area lithologies. Rutile has similarhydraulic and diagenetic behaviour as zircon, and Morton andHallsworth (1994) therefore introduced the rutile–zircon index(RuZi) for provenance characterisation, defined as:

RuZi =Rutile

Rutile + Zircon

� �× 100

with rutile and zircon given as counts per sample. This index is basedon the premise that ratios of minerals with similar hydraulic anddiagenetic behaviour most likely reflect provenance characteristics(Morton and Hallsworth, 1994). Use of the rutile–zircon index as aguide to provenance is especially important in clastic sediments thathave undergone advanced burial diagenesis and hence may have lostsignificant amounts of provenance information (Morton and Halls-worth, 1994, 1999). Sands with high RuZi indicate that rutile-bearinglithologies (metapelitic and/or metamafic rocks) are abundant in thesource region, whereas low RuZi indicates a prevalence of rutile-poorlithologies (such as igneous rocks). Since rutile and zircon are bothstable minerals (Pettijohn, 1941; Hubert, 1962; Morton and Halls-worth, 1994, 1999), RuZi values can also reflect inheritance from pre-existing clastic sediment. To date, the method has successfully beenapplied in several conventional heavy mineral studies (e.g. Whithamet al., 2004; Morton et al., 2005; Morton and Chenery, 2009).Sophisticated methods for rutile provenance characterisation are dis-cussed in Section 4.

3.4. Rutile in extraterrestrial rocks

Rutile has also been described from extraterrestrial material suchas lunar rocks and meteorites. Extraterrestrial rutile can have severalorigins, such as reduction from ilmenite, exsolution from chromiteand primary crystallisation as a minor accessory mineral (Buseck andKeil, 1966; Harper, 1996). Rutiles from lunar rocks were described, forexample, in Apollo 11, 12, 14 and 17 samples (Keil et al., 1970; Woodet al., 1970; Marvin, 1971; Hlava et al., 1972; Hill et al., 2006). Theyoccur within ilmenite as thin exsolution lamellae of less than 2 μm(Keil et al., 1970) and 2–5 μm (Wood et al., 1970) in size. They alsooccur as small anhedral grains less than 20 μm in diameter adjacent toor enclosed by ilmenite (Keil et al., 1970; Marvin, 1971; Hlava et al.,1972). Marvin (1971) identified a niobium-enriched mineral fromlunar rocks and soils, which was a niobian rutile (6.4% Nb2O5) in amicrobreccia fragment of an Apollo 12 sample. That rutile was alsoenriched in Ta, La and Ce. Hlava et al. (1972) found niobian rutile (7.1%Nb2O5) in a lithic fragment of KREEP composition (K — potassium,


REE — rare earth elements and P — phosphorus) with basaltic texturein an Apollo 14 sample.

One of the pioneers studying meteoritic rutile was Paul Ramdohrwho identified rutile in the Mt. Browne chondrite and in severalmesosiderites (Ramdohr, 1963, 1965). El Goresy (1965) mentioned aeuhedral rutile crystal enclosed in troilite of the Odessa ironmeteoriteand accessory rutile in the Dalgaranga iron meteorite. Buseck and Keil(1966) described rutile associated primarily with ilmenite andchromite from several meteorites (Allegan, Bondoc, Esterville, Farm-ington and Vaca Muerta) (see Kimura et al., 1991). Rutile is mostabundant in the Farmington L-group chondrite where it occurs in finelamellae in polycrystalline ilmenite (Buseck and Keil, 1966). Referringto Ramdohr (1963, 1965), Buseck and Keil (1966) suggested that thisrutile was derived from ilmenite breakdown due to the followingreaction:

2FeTiO3→2TiO2 þ 2Fe þ O2

Experimental studies revealed that ilmenite could not coexist withrutile and remain stable at high temperatures as they react to formFeTi2O5 (Fig. 3), a mineral in the pseudobrookite solid solution series(MacChesney andMuan, 1959; Buseck and Keil, 1966). During coolingpseudobrookite decomposes to rutile+ilmenite at and below 1140±10 °C (Lindsley, 1965), indicating that the mineral assemblage ob-served in the Farmington meteorite formed below that temperature(Buseck and Keil, 1966).

In the Vaca Muerta mesosiderite the rutile occurs together withilmenite and chromite, both in thin bands within ilmenite (Kimura etal., 1991) and in fine lamellae in chromite, as well as in individualgrains of up to 65 μm in diameter (Buseck and Keil, 1966). Nazarov etal. (2002) reported rutile from the Dhofar 303 lunar highlandmeteorite. El Goresy (1971) described Nb-rich rutile from the Tolucairon meteorite in both silicate-bearing and silicate-free sulphideinclusions. Later, Harper (1996) also analysed niobian rutiles from thismeteorite and discovered formerly live 92Nb, which forms in super-novae by p-processes (Harper, 1996) and decays by electron captureto 92Zr with a half-life of about 36 Ma (Nethaway et al., 1978).Extraterrestrial rutile may therefore bring quantitative data for theinitial abundance of short-lived, now extinct, radionuclides (e.g. 92Nb)in the solar system's parental molecular cloud, which has been thesubject of recent discussion (Schönbächler et al., 2002, 2005;Wadhwaet al., 2007, and references therein). The most interesting applicationof short-lived radionuclides is their potential usage as fine-scalechronometers to study processes in the early solar system (Harper,1996; Wadhwa et al., 2007).

4. Applications of rutile in earth sciences

4.1. Rutile geochemistry

4.1.1. IntroductionRutile is a major host mineral for Nb, Ta and other HFSE, which are

widely used as geochemical fingerprints of geological processes suchas magma evolution and subduction-zone metamorphism (e.g. Foleyet al., 2000; Rudnick et al., 2000). Although Nb/Ta values of crustal andmantle rocks have been studied for a long time, processes that lead tothe fractionation of Nb and Ta and to the formation of the Earth'shidden suprachondritic Nb/Ta reservoir are still the subject of a livelydebate, as outlined in Section 4.1.3.

Besides its application in igneous and metamorphic petrology,rutile geochemistry can also be applied in sedimentary provenancestudies. Banfield and Veblen (1991) were one of the first whosuggested that rutile geochemistry may be useful in determining theprovenance of rutile. Nevertheless, until 2002, only a few papersrelated to the mineral geochemistry of rutile and its application tosedimentary provenance studies (Götze, 1996; Preston et al., 1998,

2002)were published. This was probably because of the lack of major-element composition, in conjunction with a scarcity of rutilegeochemical data from potential source lithologies. For example,Götze (1996) suggested that rutile with elevated concentrations of Snand W implies ore-bearing source rocks. Preston et al. (1998, 2002)demonstrated that detrital rutile in Triassic continental red-beds inthe Beryl Field, North Sea, comprises almost pure TiO2, with only asmall proportion containing appreciable Nb2O5 or FeO.

More recently, however, rutile has attracted a lot of interest as newstudies have demonstrated the high potential of the trace-elementsignature of rutile, including Zr-in-rutile thermometry, for character-ising sediment source areas and hence for quantitative provenanceanalysis, as will be shown in the following sections.

4.1.2. Fe contentThe Fe content has been suggested to be an indicator of metamor-

phic origin since metamorphic rutile contains mostly N1000 ppm Fe(Zack et al., 2004a). However, lamellae-rich regions in rutile can showconsiderable Fe enrichment (Banfield and Veblen, 1991; Liou et al.,1998; Sobolev and Yefimova, 2000). Therefore, careful examination ofrutile at the microscale is necessary to ensure that measurementsyielding elevated Fe contents were carried out in a homogeneous partof the grain, as discussed in Section 2.3.

Banfield and Veblen (1991) recognised that the Fe content in rutilegenerally increases with metamorphic grade, although they cautionedthat this observation needs further research to determine whether thecorrelation is independent ofwhole-rock composition and other aspectsof metamorphic history. They suggested the potential of such acorrelation might be applicable as a thermometer in rocks that haveexperienced temperatures less than 500 °C. However, rutile formed atlow temperatures (less than 450 °C, hydrothermal) also contains highconcentration (N0.5 wt.%) of Fe (Putnis, 1978; Putnis andWilson, 1978;Müller and Halls, 2005), which suggests that the Fe content cannot beused to identify metamorphic rutile in heavy mineral separates.

Dawson and Smith (1977) assumed that their mica–amphibole–rutile–ilmenite–diopside (MARID) group of xenoliths resulted fromcrystallisation of an oxidised magma in the uppermost mantle, andthat all the Fe in rutile from these rocks is trivalent. Sobolev andYefimova (2000) noted that the Fe content in rutile from crustal andmantle eclogites and diamond inclusions depends on whole-rockcomposition, oxygen fugacity (fO2) and pressure and temperatureconditions. Hence, it is worthwhile to calculate the ferric Fe content ofrutile by either partitioning themeasured total iron content into Fe2O3

and FeO using the stoichiometric method of Droop (1987) or by usingMössbauer spectroscopy. The Fe+3 content is controlled by fO2 (e.g.Buddington and Lindsley, 1964), and thus, presence of Fe+3 indicateshigh fO2 during crystal growth. For example, many ultrahightemperature (UHT) terrains contain oxidised (high fO2) mineralassemblages (Harley, 2008, and references therein). Zhao et al. (1999)used fO2 as barometer for rutile–ilmenite assemblages in mantlexenoliths from kimberlites.

4.1.3. Nb and Ta contentsNb and Ta have the same oxidation state and nearly identical ionic

radii (Shannon, 1976; Tiepolo et al., 2000; Fig. 8) and thus shouldremain tightly coupled during chemical processes within the crust–mantle system. This should lead to relatively constant Nb/Ta ratios ofminerals and rocks, close to the chondritic value of about 17.65(McDonough and Sun, 1995). However, continental crust, island arcvolcanic rocks and many oceanic basalts are characterised bysubchondritic Nb/Ta values (e.g. Green, 1995; Rudnick and Fountain,1995; Rudnick et al., 2000; Foley et al., 2002; Schmidt et al., 2009). Ageochemically complementary reservoir is therefore required toaccommodate the mass imbalance in Nb and Ta between continentalcrust and depleted mantle (McDonough, 1991; Rudnick et al., 2000).

Fig. 11. Nb versus Cr discrimination diagrams for rutile from different metamorphiclithologies. (a) According to Zack et al. (2004b). Note that rutile from felsic granulitefacies rocks can have exceptionally high Nb contents up to 28,000 ppm and more.(b) According to Triebold et al. (2007). Positive log(Cr/Nb) values mostly indicate ametamafic source for rutile while negative values suggest derivation from metapeliticrocks. (c) According to Meinhold et al. (2008). Note that Zack et al. (2002, 2004b)introduced the terms “metamafic” and “metapelitic” to discriminate the rutile source,although, for simplification, it seems more appropriate to use the terms “mafic” and“felsic” respectively.


The processes leading tomajor fractionation of Nb and Ta, and thusto subchondritic Nb/Ta values, have been the subject of prolongeddebate because they are important for understanding the formation ofthe continental crust (e.g. Foley et al., 2002; Xiao et al., 2006). Asoutlined in Section 3.1, rutile is a major accessory mineral in eclogite,which mainly forms by subduction of gabbroic or basaltic rocks togreat depths. During metamorphic recrystallisation, rutile crystallisesfrom Fe–Ti oxides and Ti-bearing silicates. It dominates the budget ofNb and Ta in eclogite, and thus Nb/Ta of whole-rock eclogite reflectsthis ratio in rutile (Rudnick et al., 2000; Zack et al., 2002). Experimentalstudies by Brenan et al. (1994) have shown that a small amount ofrutile (∼0.2 wt.%) is enough to prevent HFSE enrichment in themantlewedge by fluids generated during subduction zone metamorphism.Thus, rutile has long been regarded as a major factor controlling theslab-to-mantle flux of HFSE (e.g. Brenan et al., 1994; Green, 1995).Subchondritic Nb/Ta of the continental crust and island arc volcanicrocks has been ascribed to melting of subducted slabs in the presenceof rutile (e.g. Rudnick et al., 2000). Rudnick et al. (2000) suggested thatrefractory eclogite produced by slab melting is the “missing reservoir”to accommodate the mass imbalance in Nb/Ta between continentalcrust and depleted mantle. This reservoir possibly exists in the Earth'sdeep mantle (Rudnick et al., 2000). Alternatively, it may be in theEarth's core (Wade and Wood, 2001).

Experimental studies on the partitioning of Nb and Ta betweenrutile andmelts have shown that rutile favors Ta over Nb (e.g. Foley etal., 2000, 2002; Klemme et al., 2005). Consequently, partial melting ofsubducted rutile-bearing eclogite with chondritic Nb/Ta results inmelts with suprachondritic Nb/Ta and a residue depleted in Nb thatcannot be the “missing reservoir” with suprachondritic Nb/Ta (e.g.Foley et al., 2002; Klemme et al., 2005).

Xiao et al. (2006) studiedNb and Ta in eclogites from theDubi–SuluUHP metamorphic belt in east-central China and suggested thefollowing model: During the early stage of subduction, hotter regionsof the subducting slab will experience significant dehydration in thepresence of amphibole and absence of rutile (b15 kbar; Fig. 10), whichleads to suprachondritic Nb/Ta in the residual amphibole eclogiteswith complementary subchondritic Nb/Ta in the released fluids. Alarge proportion of these fluids (containing Nb, Ta, Ti, etc.) can beretained in cold regions inside the subducting slab, forming hydratedcold eclogiteswith subchondritic Nb/Ta. Subduction continues and theslab, consisting of these hydrated cold eclogites, reaches greaterdepthswhere rutilefinally appears (N15 kbar; Fig. 10) and controls theNb and Ta budget. Thus, melting of these hydrated cold eclogites willform magmas with negative Nb and Ta anomalies and subchondriticNb/Ta values. Because early-dehydrated slabwith suprachondritic Nb/Ta rations cannot be melted, refractory residual eclogites have highlyvariable Nb/Ta from subchondritic to suprachondritic (Xiao et al.,2006). Nonetheless, Xiao et al. (2006) suggested that they form thegeochemically complementary reservoir to the continental crust sincetheir overall average Nb/Ta is suprachondritic.

4.1.4. Cr and Nb contentsZack et al. (2002, 2004b) suggested that Cr and Nb abundances in

rutile (Fig. 11a) can effectively distinguish between metamafic andmetapelitic source lithologies. For simplification, Triebold et al. (2007)introduced log(Cr/Nb) values to discriminate between metamafic andmetapelitic source lithologies (“1:1” line; Fig. 11b). This method isapplicable except for low Cr and low Nb contents. Based on literaturedata of Nb/TiO2 ratios of whole rock for pelites, Zack et al. (2002,2004b) calculated that rutile in metapelites contains 900–2700 ppmNb. Combined with reference data, Meinhold et al. (2008) proposedthat the lower limit of Nb in metapelitic rutiles should be set at800 ppm and that the discriminant boundaries between metamaficand metapelitic source lithologies should therefore be modified asshown in Fig. 11c. Rutiles with CrbNb accompanied by NbN800 ppmare interpreted to be derived frommetapelitic rocks (e.g. mica-schists,

paragneisses, felsic granulites). Rutiles with CrNNb and those withCrbNb, the latter however accompanied by Nbb800 ppm, areinterpreted to be derived from metamafic rocks (e.g. eclogites andmafic granulites). Rutiles from amphibolites plot in both fieldsbecause the protoliths of amphibolites are of either sedimentary ormafic igneous origin.

4.1.5. Other trace elementsSmythe et al. (2008) noted that Mg and Al contents distinguish

rutile derived from crustal andmantle sources (Fig. 12), and Al, Cr andNb contents further allow distinction between various mantle-derived rocks such as eclogite, metasomatic rutile-dominated nodulesand mica–amphibole–rutile–ilmenite–diopside (MARID: Dawson and

image of Fig.�11

Fig. 12. Discrimination between rutile derived from crustal and mantle sources,according to Al and Mg contents in rutile (after Smythe et al., 2008).

Table 2List of natural rocks containing rutile with economically important elements (compiledfrom Williams and Cesbron, 1977; Scott, 1988; Urban et al., 1992; Clark and Williams-Jones, 2004; Scott, 2005). For example, elevated concentrations of W and Sb in rutilestrongly suggest a source from a mesothermal gold deposit (see Fig. 13). The V contentin rutile can be used as a guide to mineralisation even in highly weathered rocks (Scott,2005). Geochemical data of rutile from ancient and modern clastic sedimentary rockscan therefore provide useful fingerprints to identify the type of mineralisation.

Type of deposit Characteristic elements in rutile

Volcanogenic massive sulphide Cu–Zn deposits Sn (W and/or Cu)Mesothermal and related gold deposits Sb, W and/or VMagmatic–hydrothermal Pd–Ni–Cu deposits Ni, CuGranite-related Sn deposits Sn, WGranite–pegmatite Sn–W deposits Sn, W, Nb, TaPorphyry and skarn Cu and Cu–Au deposits Cu, W (and sometimes V)


Smith, 1977) xenoliths. Magnesium is one of the least compatibleelements in rutile (see Fig. 8). Therefore, Mg-rich rutile is most likelyto be found under HP and UHP conditions and hence in mantle rocks.Moreover, rutile frommantle rocks (e.g. diamondiferous eclogite) cancontain an elevated Al content, which can be explained by a number oftiny rods of corundum (Sobolev and Yefimova, 2000). These rods aresmaller than the electron beam size a mixture of them and rutile isanalysed.

Besides the major discriminants, Cr and Nb, there are also othertrace elements that can characterise the source of rutile. For example,when elements such as V, Ni, Cu, Sn, Sb and W are detected in highconcentration in rutile, they can be considered to be anomalous andsuggest a source from metallic ore deposits (e.g. Urban et al., 1992;Clark and Williams-Jones, 2004; Scott, 2005) (Fig. 13). For instance,rutile from mesothermal gold mineralisation commonly containsbetween 0.12 and 5.9 wt.% WO3. Table 2 shows a compilation ofvarious rutile-bearing deposits and the characteristic trace elementsincorporated into the rutile crystal lattice.

4.1.6. ExamplesAs outlined in Section 4.1.3, Nb and Ta concentrations in rutile

allow tracing the formation and evolution of the continental crust.Hence, a large number of publications exists discussing Nb and Tavalues and Nb/Ta ratios of crustal and mantle rocks and the Earth's

Fig. 13. Summary of Ti, Fe, Cr, V andW contents of rutile from variably metamorphosedmesothermal gold deposits (after Clark and Williams-Jones, 2004).

hidden suprachondritic Nb/Ta reservoir. Here, the reader is referred toa selection of recent literature for further information (e.g. Xiao et al.,2006; Aulbach et al., 2008; Baier et al., 2008; Bromiley and Redfern,2008; Schmidt et al., 2009).

Since the work of Zack et al. (2004b), rutile geochemicalconstraints on sediment provenance have been included in severalpublications related to sedimentary strata from the Neoproterozoic tothe Holocene worldwide.

Stendal et al. (2006) used rutile geochemistry to establish that therutiles in young alluvial and eluvial heavy mineral deposits of theYaoundé region in southern Cameroon were derived from theadjacent Neoproterozoic micaschists of the Yaoundé Group.

Triebold et al. (2007) analysed detrital rutile from Early Palaeozoicmetasedimentary rocks and Holocene river sediments of the Erzge-birge, Germany. They demonstrated that rutile compositions in riversediments mirror those of the surrounding country rocks. This ledthem to conclude that rutile is an accurate tracer of source rockcharacterisation in sedimentary provenance studies.

Uher et al. (2007) analysed niobium–tantalum mineral assem-blages (including Nb–Ta-rich rutile) from alluvial placer deposits insouthwest Slovakia, which were most likely sourced from graniticpegmatites of the Bratislava Granitic Massif.

Meinhold et al. (2008) investigated detrital rutile from Carbonif-erous to Early Triassic sandstones of Chios Island, Greece. Theyrecognised a change in source rock lithology from the Carboniferouswith dominantly metamafic rutile to the Early Triassic with moremetapelitic rutile. Zr-in-rutile thermometry has confirmed thischange in the sediment source, which was explained by plate-tectonicreorganisation during the subduction of Palaeotethys at the southernmargin of Laurussia in the Late Palaeozoic (Meinhold et al., 2008).

Morton and Chenery (2009) studied the rutile source of Jurassic toPalaeocene sandstones in hydrocarbon exploration wells of theNorwegian Sea. Their rutile data confirm the presence of five distinctsand types sourced from different parts of the Norwegian andGreenland landmasses to the east and west of the basin, establishedby previous studies, concentrating on provenance-sensitive heavymineral ratios, garnet geochemistry, tourmaline geochemistry anddetrital zircon geochronology (Morton and Chenery, 2009). Moreover,these authors demonstrated the importance of rutile geochemistry asa provenance tracer, since the method yields diagnostic data onsource rock lithology and metamorphic facies even in highly modifiedsandstones that may have lost significant amounts of provenanceinformation. This is because of the ultrastable nature of rutile underboth diagenetic and surficial weathering conditions (Pettijohn, 1941;Hubert, 1962; Morton and Hallsworth, 1999, 2007).

Although the successful application of rutile geochemistry tosingle-mineral provenance studies has been shown above, there are atleast two publications that clearly demonstrate that the discrimina-tion diagrams based on Cr and Nb may not be strictly valid. Bakun-Czubarow et al. (2005) pointed out that the Cr–Nb discrimination

image of Fig.�12

image of Fig.�13


diagram of Zack et al. (2002, 2004b) is not applicable for rutile fromthe Sudetes Fe–Ti-rich eclogites, which plot in the metapelite field.Rutiles from eclogite of the ultrahigh-pressure metamorphic area atthe Saidenbach reservoir of the Erzgebirge in Germany (Massonne,2001) also plot in the field of metapelitic source lithologies (Trieboldet al., 2007; their fig. 5). Based on whole-rock geochemical data,Massonne and Czambor (2007) suggested that the protoliths of theSaidenbach eclogites were basaltic to trachyandesitic in compositionand formed in a within-plate geotectonic setting with a relatively lowdegree of melting. The Saidenbach eclogites have high Nb/Ti ratios.Rutile dominates the Nb and Ti budget in eclogites, and rutiles in theSaidenbach eclogites inevitably have high Nb concentrations, andthus, they plot in the field for metapelitic rutile. Despite theseshortcomings, the Cr–Nb discrimination diagram, as it stands now, isuseful and should be applied in sediment provenance analysis untilmore rutile data of various source rock lithologies are available toplace better constraints on its discrimination boundaries.

4.2. Zr-in-rutile thermometry

4.2.1. IntroductionThe partitioning of zirconium (Zr) into rutile coexisting with

zircon or other Zr-rich phases has a strong dependence ontemperature (T) (Zack et al., 2004a; Watson et al., 2006; Tomkins etal., 2007). Zack et al. (2004a) were the first presenting an empiricallycalibrated Zr-in-rutile thermometer (Fig. 14), expressing temperatureas:

T BCð Þ = 127:8 × ln Zrppm� �

−10

with an error of ±50 °C. The calibration is based on analyses of rutilegrains from 31 metamorphic rocks with rutile–quartz–zircon assem-blages spanning a temperature range from 430 to 1100 °C.

Watson et al. (2006) presented a revised Zr-in-rutile thermometerbased on experimental data (at ∼10 kbar) and constrained by naturalrutiles from metamorphic rocks (Fig. 14), expressing temperature as:

T BCð Þ = 44707:36− log10

Zrppm� �

−273

with an error of ±20 °C. The two thermometers intersect at a tem-perature of about 540 °C but diverge significantly both at lower andhigher temperatures (Fig. 14). Watson et al. (2006) considered thisbehaviour to indicate possible pressure dependence and emphasisedthe need for further investigation.

Fig. 14. Comparison of Zr-in-rutile thermometers of Zack et al. (2004a), Watson et al.(2006) and Tomkins et al. (2007). For the latter thermometer, only calculations at 10,30 and 60 kbar are shown.

Ferry and Watson (2007) suggested that the Zr content of rutiledepends on the activity of SiO2 as well as temperature, which hadbeen confirmed by experimental data. This observation let them toconclude that the Zr-in-rutile thermometer may now be applied torocks without quartz, if the activity of SiO2 is estimated. Themaximum introduced uncertainty by unconstrained activity of SiO2

was given with about 60–70 °C at 750 °C (Ferry and Watson, 2007).The new calibration of the Zr-in-rutile thermometer is remarkablysimilar to that described by Watson et al. (2006). Ferry and Watson(2007) gave examples showing that the Zr contents of rutile thatrecord 1100, 750 and 500 °C using the thermometer of Watson et al.(2006) record 1093, 750 and 502 °C with the revised calibration for anactivity of SiO2=1. Ferry and Watson (2007) also gave a preliminaryevaluation of the dependence of Zr-in-rutile thermometers onpressure.

Tomkins et al. (2007) discussed the pressure dependence, alreadyemphasised by Watson et al. (2006), and presented three new Zr-in-rutile thermometers based on experimental data (Fig. 14). Theyclearly demonstrate that pressure, especially ultrahigh pressure (seealso discussion in Chen and Li, 2008), does have an effect on theuptake of Zr in rutile. The new thermometer equations by Tomkins etal. (2007) are, in the α-quartz field

T BCð Þ = 83:9 + 0:410 × P

0:1428−R × ln Zrppm� �−273

in the β-quartz field

T BCð Þ = 85:7 + 0:473 × P

0:1453−R × ln Zrppm� �−273

and in the coesite field

T BCð Þ = 88:1 + 0:206 × P

0:1412−R × ln Zrppm� �−273

with P in kbar, and R is the gas constant, 0.0083144 kJ K−1. An obviousinput parameter in their equation is the pressure. Hence, thisthermometer is suitable for rutiles of known source, meaning ofknown pressure during rutile crystallisation. For detrital rutile,however, the pressure under which the source rock had formed iscommonly unknown. To avoid speculation about the input parameter‘pressure’, the equation of Watson et al. (2006) should be used fordetrital rutile or for rutile of unknown origin in general. Although itwas originally thought that the Zr-in-rutile thermometer is only validfor metapelitic rutile (Zack et al., 2004a), recent studies havedemonstrated that it is also valid for rutile frommetamafic lithologies(e.g. Zack and Luvizotto, 2006; Triebold et al., 2007) and for detritalmetamafic rutile (e.g. Meinhold et al., 2008; Morton and Chenery,2009).

Chen and Li (2008) have shown that the Zr-in-rutile thermometersbyWatson et al. (2006) and Tomkins et al. (2007) yield similar shapes ofthe frequency histograms of temperatures (Fig. 15). However, the Zr-in-rutile thermometer of Watson et al. (2006) gives about 70 °C lowertemperatures compared with the Zr-in-rutile thermometer of Tomkinset al. (2007) for eclogitic rutile from the centralDabieUHPmetamorphiczone. The thermometer of Zack et al. (2004a) shows a wider spread inthe frequency histograms of temperatures. The differences in shape andrange of the frequency histograms of temperatures reflect the differentapproaches of the various Zr-in-rutile thermometers to calculate thetemperature. Hereby, the pressure dependence of Zr incorporation intothe rutile crystal lattice is an important factor to be considered, which iswell illustrated in Fig. 14. The thermometers of Zack et al. (2004a) andWatson et al. (2006) intersect at a temperature of about 540 °Cbut diverge significantly both at lower and higher temperatures. The

image of Fig.�14

Fig. 15. Frequency histograms (bin width=25 °C) showing calculated formationtemperatures for eclogitic rutile from the central Dabie UHP metamorphic zone withdata from Chen and Li (2008). Abbreviations TZ, TW and TT correspond to the Zr-in-rutilethermometers of Zack et al. (2004a), Watson et al. (2006) and Tomkins et al. (2007)respectively. TZ was calculated from Eq. (3) in Zack et al. (2004a); TT was calculated at28 kbar. Besides histograms, some statistical parameters are also given. n — number ofdata used,Min—minimun value,Max—maximum value,Med—Median, Avg— average(arithmetic mean), Std — Standard deviation (1σ), Sk — Skewness, Ku — Kurtosis.


thermometer ofWatson et al. (2006) gives nearly identical results to thethermometer of Tomkins et al. (2007) using the α-quartz equation at10 kbar, which is the pressure at that the Zr-in-rutile thermometer ofWatson et al. (2006)was experimentally calibrated. In the temperaturerange between 750 °C and 1150 °C the thermometer of Zack et al.(2004a) yields comparable results to the Tomkins et al. (2007) coesite-field equation at 30 kbar. Nonetheless, the thermometer of Zack et al.(2004a) shows a wider spread in the frequency histograms oftemperatures (Chen and Li, 2008;Meinhold et al., 2008)which supportsthe use of the Zr-in-rutile thermometer of Watson et al. (2006) forsediment provenance studies of detrital rutile. Baldwin and Brown(2008) explain the trend that the Zr-in-rutile thermometer of Zack et al.(2004a) always gives a higher temperature than, for instance, the

thermometer of Tomkins et al. (2007) with overestimation of themaximum temperature point for the Zack et al. (2004a) empiricalcalibration.

In general, overestimation of temperature with Zr-in-rutilethermometry is only possible where mineral assemblages in equilib-rium with rutile are quartz-free while underestimation can occur byabsence of zircon and/or in partly reset mineral assemblages (Zack etal., 2004a; Baldwin and Brown, 2008; Harley, 2008; Luvizotto andZack, 2009). Although Tomkins et al. (2007) noted that “Zr-in-rutilethermometry is not going to be a magic bullet in thermometry”,clearly it is an attractive method to calculate temperatures of high-grade and ultrahigh-grade metamorphic rocks (Spear et al., 2006;Zack and Luvizotto, 2006; Miller et al., 2007; Baldwin and Brown,2008; Harley, 2008; Luvizotto and Zack, 2009). In the case of detritalrutile, Zr-in-rutile thermometry is an important technique insediment provenance analysis especially in highly modified sand-stones that may have lost significant amounts of provenanceinformation (Morton and Chenery, 2009).

4.2.2. ExamplesThe reliability of the new Zr-in-rutile thermometers of Zack et al.

(2004a) was demonstrated, for example, for eclogites and granulitesfrom the Sudetes of SW Poland (Bakun-Czubarow et al., 2005) and for awide variety of eclogites from Germany, Greece, Italy, Norway,Switzerland and Turkey (Zack and Luvizotto, 2006). Spear et al. (2006)showed the successful application of theWatson et al. (2006) calibrationon blueschist facies rocks from Sifnos Island, Greece and Vaggelli et al.(2007) on high-pressure rocks from the Western Alps, Italy.

Zack et al. (2004b) first applied the combined use of detrital rutilegeochemistry and Zr-in-rutile thermometry for quantitative sedimentprovenance analysis. Subsequent studies by Triebold et al. (2007) andvon Eynatten et al. (2005) have demonstrated that the trace elementcomposition of detrital rutile is unrelated to the grain size of the hostsediment. They furthermore revealed that high-grade metamorphicrutile might preserve its geochemical signature to much lowertemperatures, suggesting that rutile may survive metamorphic condi-tions on a retrograde path below 550 °C. Stendal et al. (2006) have alsoshown that relic rutile can retain its original composition during low- tomedium-grade metamorphism, indicating that it can survive tempera-tures as high as 620 °C. Thus, the generally accepted views of rutilebreakdown during low-grade metamorphism at greenschist facies andformation duringmedium-grademetamorphic conditions (Force, 1980;Zack et al., 2004b)may not be strictly valid. Luvizotto et al. (2009a)whorecognised prograde rutile growth from ilmenite in low- to medium-grademetasedimentary rocks of the Erzgebirge, Germany, as outlined inSection 3.1, have recently addressed this subject.

Meinhold et al. (2008) compared results obtained by using the Zr-in-rutile thermometers of Zack et al. (2004a) andWatson et al. (2006)on detrital rutile from Carboniferous to Early Triassic sandstones ofChios Island, Greece. They demonstrated the discrepancy betweenboth thermometers, with the Zr-in-rutile thermometer of Zack et al.(2004a) giving a wider spread in the frequency histograms oftemperatures compared with the thermometer of Watson et al.(2006),whichwas also pointedout byChen and Li (2008), as discussedin Section 4.2.1.

Morton and Chenery (2009) successfully used Zr-in-rutile ther-mometry to characterise the rutile source of Jurassic to Palaeocenesandstones in hydrocarbon exploration wells of the Norwegian Sea,accompanied with application of rutile geochemistry, as outlined inSection 4.1.6.

Note that for provenance identification of detrital rutile thepossibility of polyphase recycling has to be kept in mind.

4.2.3. Zr diffusionCherniak et al. (2007b) studied the Zr diffusion in natural and

synthetic rutile and provided evidence that Zr concentrations in rutile

image of Fig.�15

Fig. 16. Zr centre-retention criteria for rutile of different radii cooling at a linear ratefrom a range of maximum temperatures (after Cherniak et al., 2007b). The criticalcooling rate depends on the maximum temperature, grain radius and diffusionparameters. When cooling rates are slower than this critical value, the peak-temperature Zr signature in the centre of a rutile grain is not preserved over thecooling path. For illustration purposes, the field of ultrahigh-temperature (UHT)metamorphism (Harley, 1998) is marked in grey.

Fig. 17. Dependence of the closure temperature for O isotope exchange in rutile fromcrystal size and cooling rate (after Moore et al., 1998).


can be affected by later thermal disturbance, although, based onobservations made by Watson et al. (2006), this is not likely to be asrapid as Sasaki et al. (1985) suggested. Cherniak et al. (2007b) pointedout that Zr diffusion in rutile is significantly slower than diffusion ofdivalent and trivalent cation substitutions and seems little affected byvariations in trace element composition. The authors, however, madea cautionary remark that under a broad range of geological conditions,the Zr-in-rutile thermometry is less resistant to resetting than Ti-in-zircon and Zr-in-titanite thermometry. They demonstrated that Zrdiffusion in rutile depends on the grain size and the cooling rate(Fig. 16). For example, a rutile grain formed under ultrahigh-temperature (UHT) metamorphic conditions at about 945 °C with agrain radius of 500 μm will preserve its Zr signature in the centre ofthe grain when the cooling rate exceeds 100 °C Ma−1. Hence, rutileformed under UHT conditions will retain its Zr signature only undercertain circumstances such as rapid cooling (Cherniak et al., 2007b;Fig. 16). Therefore, UHT source lithologies may be underestimated insedimentary provenance studies with Zr-in-rutile thermometry. Chenand Li (2008) analysed eclogitic rutile from the Dabie–Sulu UHPmetamorphic zone in east-central China and suggested that retro-gression (with fluid presence) can release Zr from the rutile crystallattice. This consequently causes lower calculated temperatures anddoes not provide the peak metamorphic temperature. Luvizotto andZack (2009) observed large spreads in Zr concentrations for rutilegrains from granulite facies metapelitic rocks of the Ivrea–VerbanoZone, Southern Alps, which they explained by Zr mobilisation due toslow cooling rates and/or fluid presence. All these points have to bekept in mind when using Zr-in-rutile thermometry.

4.3. Oxygen isotopes

4.3.1. IntroductionThe oxygen (O) isotope composition of minerals can yield infor-

mation regarding theextent andnatureoffluid–mineral interactionsandthe temperature at the timeof crystallisationor alteration (e.g.Matthewset al., 1979;Agrinier, 1991; Zheng, 1991; Chackoet al., 1996;Moore et al.,1998; Zhenget al., 1999, 2003).Many studies have shown thatO isotopesare a good fingerprint to identify the derivation of certain minerals from

juvenile mantle-derived magmas, which contrast with those from“contaminants” that experienced low temperature and surficial processsuch as hydrothermal alteration and sedimentary recycling and hencehave elevated δ18O values (e.g. Mojzsis et al., 2001; Wilde et al., 2001;Valley, 2003; Valley et al., 2005). The isotopes used are 18O and 16O,which are incorporated into the lattice during crystallisation. In currentstudies, oxygen isotope analyses on minerals are commonly performedby secondary ion mass spectrometry (SIMS) (e.g. Valley, 2003) andvarious laser techniques (e.g. Li et al., 2003; Valley, 2003; Zhang et al.,2006). The O isotope composition of a mineral is reported in deltanotation (δ18O) relative to VSMOW (Vienna Standard Mean OceanWater), which has an 18O/16O value of (2005.2±0.45)×10−6 (Gon-onfiantini, 1978). The corresponding equation is as follows:

δ18O =

18O =16O

� �sample

18O =16O� �

VSMOW

−1

264

375 × 103

with δ18O values in per mil (‰).Experimental studies by Moore et al. (1998) on synthetic and

natural rutile have shown that the closure temperatures for Odiffusion in rutile are high (Fig. 17), with about 650 °C for a crystalwith a 100-μm radius and a cooling rate of 10 °C Ma−1. That means arutile crystal with a 100-μm radius loses its initial core compositiononly after heating at 600 °C for just over 10 Ma. Moore et al. (1998)finally concluded that rutile retains its O isotope composition during awide range of thermal events.

Various minerals effectively fractionate the O isotopes. As for allstable isotopes, this fractionation process is a strong function oftemperature and is time-independent. For example, quartz, calcite andalbite more strongly partition 18O while diopside, hornblende, zircon,almandine and rutile more strongly partition 16O (Matthews et al.,1979; Chacko et al., 1996; Moore et al., 1998, and references therein).Fig. 18 demonstrates the O isotope fractionation in a coesite-bearingeclogite of the Dabie Mountains, with δ18O values of about +1.1‰ forquartz, −2.3‰ for garnet and −6.1‰ for rutile (Li et al., 2003). Acompilation of literature data reveals that eclogitic rutile shows δ18Ovalues from−8.9 to +7.1‰, with values from 3.6 to 8.0‰ for oxygenisotope fractionation between quartz and rutile (Fig. 19). Fig. 20compares the quartz–rutile geothermometers of Agrinier (1991),Zheng (1991) andChacko et al. (1996). Quartz–rutile geothermometryis a reliable method because both minerals are relatively resistant topost-formation oxygen exchange (Agrinier, 1991; Chacko et al., 1996).

image of Fig.�16

image of Fig.�17

Fig. 18. Oxygen isotope composition of garnet, quartz and rutile from a coesite-bearingeclogite of the Dabie Mountains. Data were taken from Li et al. (2003). Fig. 20. Comparison of the quartz–rutile oxygen isotope geothermometers of Agrinier

(1991), Zheng (1991) and Chacko et al. (1996).


Quartz–rutile geothermometry yields reliable temperatures for blues-chist and eclogite facies rocks but may not work for granulite faciesrocks due to extensive re-equilibration (Chacko et al., 1996).

4.3.2. ExamplesVogel and Garlick (1970) analysed the O isotope composition of

various minerals, amongst others rutile and quartz, from eclogites inEurope, Venezuela and California, and they pointed out that O isotopefractionations between quartz and rutile are relatively large. Thus, thequartz–rutile pair is particularly suitable for geothermometry becauseanalytical errors involved in the determination of δ18O values would

Fig. 19. Cross plot showing δ18O values of rutile and quartz–rutile fractionation valuesin various eclogites (n=38). The frequency histogram (bin width=0.5‰) shows thedistribution of quartz–rutile fractionation values. Data were taken from Vogel andGarlick (1970), Desmons and O'Neil (1978), Matthews et al. (1979), Agrinier et al.(1985), Zheng et al. (1999), Li et al. (2003) and Gao et al. (2006). The terms ‘hot’ and‘cold’ refer to the temperature conditions during eclogite facies metamorphism, basedon quartz–rutile geothermometry. Note that a number of samples from the ‘cold’eclogite suite experienced retrograde isotope exchange subsequent to the eclogitefacies metamorphism (see Section 4.3.2).

not lead to large errors in the calculated isotope temperatures(Matthews et al., 1979). Hence, Addy and Garlick (1974) andMatthews et al. (1979) carried out experimental studies of O isotopefractionation between rutile and water and tested their quartz–rutilegeothermometers on a number of eclogites. Desmons and O'Neil(1978) reported O isotope data of various minerals from eclogites ofthe Western Alps, Italy, and calculated for these eclogites an averageformation temperature of 540 °C, using quartz–rutile and quartz–phengite geothermometry. Studies by Agrinier et al. (1985) haveshown that in eclogites of the WGR, Norway, the O isotopefractionation between rutile and quartz is small (Δ18O∼4.3–5.0‰),with quartz–rutile geothermometry yielding formation temperaturesof about 680 to 715 °C. Zheng et al. (1999) analysed the O isotopecomposition of various minerals (i.a. rutile and quartz) from HP andUHP eclogites of the Dabie Mountains and calculated formationtemperatures using amongst others quartz–rutile geothermometry.Quartz–rutile pairs from some of the eclogites yielded isotopetemperatures lower than the temperatures of eclogite facies meta-morphism, suggesting O isotope exchange due to retrograde fluid–rock interaction (Zheng et al., 1999). Li et al. (2003) used O isotopeanalysis of rutile to test the validity of rutile U–Pb isochron dating oncoesite-bearing eclogite from the Dabie Mountains. They determinedalmost identical δ18O values for different rutile grains from the samespecimen (Fig. 18), which suggests attainment of O isotope homog-enisation in rutile during eclogite facies metamorphism and preser-vation during amphibolite facies retrograde metamorphism (Li et al.,2003). Gao et al. (2006) also studied the O isotope composition ofmineral pairs in eclogite from the Dabie Mountains, with the quartz–rutile pair yielding an isotope temperature of 530 °C. Chen and Li(2008) emphasised the potential of quartz–rutile geothermometry toplace constraints on rutile U–Pb cooling ages since O diffusion in rutileis similar to that of Pb under hydrous conditions (Moore et al., 1998;Cherniak, 2000).

4.4. U–Pb geochronology

4.4.1. IntroductionRutile typically contains between 3 and 130 ppm of uranium

(Mezger et al., 1989) (Table 3; Fig. 21), but higher concentrations alsooccur, making Pb–Pb and U–Pb dating possible (e.g. Mezger et al.,1989, 1991; Möller et al., 2000; Vry and Baker, 2006). Radiometricdating of rutile is based on the occurrences of unstable (radioactive)uranium isotopes 238U and 235U incorporated into the rutile crystalstructure, which decay over several stages (decay chain) into stabledaughter lead isotopes 206Pb and 207Pb, respectively (Jaffey et al.,1971; Table 4). By measuring the parent/daughter ratios and known

image of Fig.�18

image of Fig.�19

image of Fig.�20

Table 3U values (in ppm) for rutile from different source lithologies compiled from literature.Note that the lowermost concentrations for U (minimum values) are defined by thedetection limit of the technique applied for analysis. Felsic granulite comprises heregranulite and granulite facies gneiss. Quartz vein data are mainly from eclogite faciesquartz veins (n=75), supplemented by low-temperature (hydrothermal) quartz veinmineralisation (n=9) and a single granitic pegmatite vein sample (n=1).

Felsic granulite Eclogite Quartz vein Metasediment

n 185 91 85 40Min 0.01 0.01 0.15 0.70Max 390 170 176 143Med 19 1 7 10Avg 24 5 9 21Std 33 22 19 27Ref (1) (2) (3) (4)

Abbreviations: n — number of data, Min — minimum value, Max — maximum value,Med—Median, Avg— average (arithmetic mean), Std— Standard deviation (1σ). Ref—References: (1) Mezger et al. (1989, 1991), Romer and Rötzler (2001), Luvizotto andZack (2009); (2) Zack et al. (2002), Li et al. (2003), Schärer and Labrousse (2003), Xiaoet al. (2006), Gao et al. (2007), Miller et al. (2007), Kylander-Clark et al. (2008); (3)Richards et al. (1988), Uher et al. (1998), Franz et al. (2001), Xiao et al. (2006), Gao et al.(2007), Kylander-Clark et al. (2008); (4) Mezger et al. (1989, 1991), Corfu et al. (1994),Möller et al. (1995, 2000), Bibikova et al. (2001), Zack et al. (2002), Luvizotto et al.(2009a).

Table 4Half-life and decay constant values of parent–daughter pairs of uranium and thorium(data from Jaffey et al., 1971; Stacey and Kramers, 1975).

Isotope decay Half-life value Decay constant

t1/2 λ(yr) (yr−1)

238U→206Pb+84He+6β− 4.4683×109 1.55125×10−10

235U→207Pb+7 4He+4β− 0.70381×109 9.8485×10−10

232Th→208Pb+6 4He+4β− 14.01×109 0.49475×10−10


decay constants, it is possible to calculate the age when rutile cooledbelow its “blocking” or closure temperature. The latter is around600 °C for rutile grains larger than about 0.2 mm in diameter(Cherniak, 2000; Vry and Baker, 2006), which is much higher thanpreviously thought (370–500 °C: Mezger et al., 1989). The mathe-matical expression to determine the age of a rutile sample, as appliedto any closed system, is given as:

t =1λln 1 +

DP

� �

where t is the elapsed time, λ the decay constant of the parent isotope,ln the natural logarithm, D the number of atoms of the daughterisotope in the sample, and P the number of atoms of the parent isotopein the sample.

Fig. 21. Box and whisker plots showing U values for rutile from different sourcelithologies. The box represents the middle 50%; the bar inside the box represents themedian. ‘Outliers’ are represented by black rectangles. n — number of data used. SeeTable 3 for references. Although included in the calculation, note that for illustrationpurpose the high U value of 390 ppm of a single granulite facies rutile grain is notshown here.

Measurements to determine the required parent/daughter ratios areperformed by conventional isotope dilution-thermal ionisation massspectrometry (ID-TIMS), secondary ion mass spectrometry (SIMS), ofwhich the sensitive high-resolution ion microprobe (SHRIMP) is anexample, and laser ablation inductively coupled plasma mass spec-trometry (LA-ICP-MS). Rutile has some advantages compared withzircon for U–Pb dating. Firstly, rutile from granulite facies rocks containsalmost no Th, allowing common lead correction via 208Pb (Allen andCampbell, 2007; Zack et al., 2008; see also Ireland andWilliams, 2003).Secondly, the isotope composition of Pb in rutile is usually highlyradiogenic, and U–Pb ages are mostly concordant (Mezger et al., 1989,1991; Mukasa et al., 1998; Möller et al., 2000; Bibikova et al., 2001).Thirdly, rutile appears to be resistant to subsequent resetting of Pbvalues (Vry and Baker, 2006).

Rutile has also some disadvantages comparedwith zircon for U–Pbdating. Rutile usually has lower U contents compared with zircon.Furthermore, there is a lack of large, isotopically homogeneous andcommonly available natural rutile standards to assess measurementmethods and demonstrate the quality of acquired geochemical data,although this may change in the future (Luvizotto et al., 2009b).

Eclogitic rutile commonly has low U contents (Table 3; Fig. 21),which in turn leads to low radiogenic Pb contents, and can contain arelatively large proportion of common (nonradiogenic) Pb (Cherniak,2000; Franz et al., 2001; Schärer and Labrousse, 2003). Therefore,common Pb correction is important in age calculation, based on theisotope composition of rutile in a single analysis (Cherniak, 2000; Li etal., 2003). Correction for common Pb for the U–Pb data can be madeusing the measured 238U/206Pb and 207Pb/206Pb ratios following Tera-Wasserburg (1972) as outlined, for example, in Williams (1998).Further possibilities are the use of a Pb growth model (Stacey andKramers, 1975) and a numerical solution if measurement of 204Pb isnot possible (Andersen, 2002). Common Pb correction is also possibleby using Pb ratios obtained from leached K-feldspars or the hostwhole-rock sample (e.g. Mezger et al., 1989). The latter method isonly applicable for rutile of known igneous ormetamorphic host rocksand not for detrital rutile. The problem of common Pb correction canbe avoided if there is the chance to construct an isochron (e.g. Schandlet al., 1990; Li et al., 2003; Stendal et al., 2006). This, however, requiresanalyses of a sufficient number of coexisting minerals with large U/Pbfractionation (e.g. Mukasa et al., 1998; Li et al., 2003; Schärer andLabrousse, 2003). Fig. 22 schematically illustrates the interpretation ofU/Pb ratios of rutile in the conventional (Wetherill) concordia plotand in a U–Pb isochron diagram.

4.4.2. ExamplesRadiometric dating of rutile has been successfully carried out for

more than two decades (e.g. Corfu and Andrews, 1986; Schärer et al.,1986; Richards et al., 1988). For example, Mezger et al. (1989) appliedthe rutile geochronometer to reconstruct the pressure–temperatureevolution of Archaean and Proterozoic high-grade polymetamorphicterrains in North America. They recognised that within a single hand-specimen larger rutile grains give older ages than do smaller ones andexplained this observation with volume diffusion directly related tothe dimensions of the rutile crystal. Mezger et al. (1989) furthermoredefined that at a cooling rate of about 0.5–1 °C Ma−1 the closure

image of Fig.�21

Fig. 22. (a) Conventional concordia plot after Wetherill (1956) illustrating the U–Pbsystematic of rutile for various stages of Pb loss. Assuming a simple two-stage history,the upper concordia intercept of a best-fit line gives the crystallisation age of the rutilewhile the lower intercept gives the age of isotopic disturbance. Discordance iscommonly caused by Pb loss due to radiation damage of the crystal structure. Schmitzand Bowring (2003) and Kramers et al. (2009) discuss causes of Pb loss in detail.(b) Schematic 238U/204Pb–206Pb/204Pb isochron diagram for a suite of co-genetic rutilegrains. For example, this method has successfully been applied by Li et al. (2003). In aclosed system, the 206Pb/204Pb ratios (y-axis) plotted against the 238U/204Pb ratios (x-axis) should ideally define a straight line, termed an ‘isochron’. This, however, isnormally not the case because of analytical uncertainties. Hence, the analytical errorsmust be considered when the best-fit line through the analytical data points isdetermined by least-squares regression techniques (York, 1967, 1969). The interceptwith the y-axis gives the initial 206Pb/204Pb ratio of the system (t=0). The slope of thebest-fit line (regression line) yields the age of the co-genetic rutile grains. Note that theinterpretation of a Pb–Pb isochron diagram is more complex (e.g. Patterson, 1956).


temperature for U–Pb diffusion in rutile is about 420 °C for grains witha radius of 90–210 μm and about 380 °C for grains with a radius of 70–90 μm. The significance of these conclusions has been debated, asdiscussed later in this section.

Romer and Rötzler (2001) analysed rutile grains from granulitefacies rocks of the Saxonian Granulite Massif. The grains had lowradiogenic Pb contents and yielded a broad range in apparent 206Pb/238U ages, which was interpreted by the authors as being due to initialisotope heterogeneity. Franz et al. (2001) and Chen et al. (2005) had asimilar problemwith eclogitic rutile fromDabie and Sulu respectively.Heterogeneity of the initial Pb isotopic composition in combinationwith the inability to make a sufficiently good common Pb correctionfor each individual rutile U–Pb analysis will lead to ambiguous results.

Wong et al. (1991) used the ID-TIMS method to carry out U–Pbisotope dating on rutile from Archaean greenstones and gold miner-alisation in theVal d'Or regionofQuebec. Theydetermined aU–Pbageof2684±7 Ma, which overlaps within the analytical error with previous40Ar/39Ar ages on hornblende (2693±17Ma and 2672±23Ma) andthus shows the successful application of U–Pb rutile dating. Hydrother-mal rutile from the alteration zone around a quartz vein gave a Pb–Pbisochron age of about 2600 Ma thatwas interpreted as the time of rutilegrowth during vein emplacement and constrains the age of goldmineralisation.

Bibikova et al. (2001) dated rutile from various rocks of theArchaean domain of the Belomorian Belt and its junction zone withthe Karelian Protocraton of the Baltic Shield. The analysed rutiles gaveconcordant U–Pb ages between 1740 and 1810 Ma and are about 50–100 Ma younger than the coexisting titanite, with smaller agedifference in the junction zone and larger age difference in the mainbody of the Belomorian Belt. The difference in U–Pb ages may reflectdifferent cooling histories of both units (see Bibikova et al., 2001 fordiscussion).

Hirdes and Davis (2002) carried out a multigrain ID-TIMS analysisof rutile from garnet-hornblende gneiss of southeastern Ghana. The206Pb/238U age of 576±2 Ma corrected for common Pb is concordantand was interpreted by them as a younger limit on metamorphismwhen the cooling isograd passed through the closure temperature ofrutile.

Li et al. (2003) reported the first high-precision U–Pb age formetamorphic rutile of about 218 Ma (ID-TIMS) from coesite-bearingeclogite of the Dabie Mountains using conventional U–Pb dating andthe isochron datingmethod (see also Chen et al., 2006). They analysedtwo colour types of rutile, light red and reddish brown, which showedno systematic difference in the concentrations of U and Pb or of Pbisotope ratios. In addition, they showed that omphacite in eclogite hasa low U/Pb ratio and thus suggested that the Pb composition ofomphacite can be used for common Pb correction in U–Pb dating ofrutile from eclogites.

Flowers et al. (2005) obtained 206Pb/238U ages of rutile (and titaniteand apatite) from aMesozoicmagmatic arc in New Zealand to constrainthe timing and duration of exhumation. Franz and Romer (2007) datedsyn-eclogite facies rutile from the Strona–Ceneri Zone of the SouthernAlps using the ID-TIMS method to constrain the tectonometamorphicevolution at the northern margin of Gondwana during Early Palaeozoictime. Further U–Pb ages of rutile (and titanite) were obtained fromeclogites of the WGR to assess the style and timing of exhumation andcooling of that UHP terrane (Kylander-Clark et al., 2008). There seem tobe fundamental differences in themechanisms controlling the evolutionof large UHP terranes (Dabie–Sulu, WGR) that undergo protractedsubduction and exhumation, and smaller UHP terranes (e.g. DoraMairain the Western Alps) that undergo rapid subduction and exhumation(Kylander-Clark et al., 2008, and references therein).

Besides isotopic dating of rutile from metamorphic rocks, anumber of studies have also been already shown the power ofradiometric rutile dating in sedimentary successions from thePalaeoproterozoic to the Holocene worldwide.

SHRIMP U–Pb work by Sircombe (1995, 1997) on rutile frommineral sands in eastern Australia has shown a predominance of LateProterozoic/Early Cambrian grains that are exotic to the local con-tinental hinterland (Williams, 1998).

Harrison et al. (2007) used a SIMS multi-collector facility todetermine 207Pb/206Pb ages of detrital rutile from the famous JackHills quartzite of Western Australia. They recognised a distinct agepeak at 2.5 Ga, which corresponds to regional metamorphism andlocal granite emplacement in the Archaean Narryer Gneiss Complex.

Stendal et al. (2006) carried out lead isotope analyses using a stepleaching process on rutile grains from alluvial heavy mineral depositsand from a Neoproterozoic garnet–kyanite micaschist of the YaoundéGroup, southern Cameroon. The 207Pb/204Pb and 206Pb/204Pb data for

image of Fig.�22


most rutiles from heavy mineral concentrates yielded scattered plotson the Pb–Pb isochron diagram, with no possibility to define a clearage. However, those from the micaschist defined an age of about950 Ma, which suggests that rutile in the Yaoundé Group formedduring early Pan-African metamorphism or was inherited as detritalrutile from an early Pan-African source (Stendal et al., 2006).

Birch et al. (2007) used LA-ICP-MS to date detrital rutile from theLate Cretaceous–Tertiary gold-bearing White Hills Gravel placerdeposits of the Victorian uplands in Australia. The analysed rutilesshow up to 5.5 wt.% Nb2O5 and 2.9 wt.% WO3 and together with theirweighted mean 206Pb/238U age of 393±10 Ma (2σ) suggest an originassociated with granite intrusion in the St Arnaud district (Birch et al.,2007).

Allen and Campbell (2007) analysed rutiles from a sand sample ofthe lower Mississippi River in the U.S.A. using LA-ICP-MS. Theyidentified a major Appalachian source and noted that some traceelements (i.e. Cr, V and Zr) show strong correlation with age. Thelatter effect is probably caused by diffusion of cation substitutions forTi4+ in the crystal lattice of rutile under slow cooling conditions (seeCherniak et al., 2007b).

Taylor (2008) used an excimer laser system coupled to aquadrupole ICP-MS to date rutile from the North Kimberley kimberliteprovince of northwestern Australia and from a present-day streamcatchment within the Georgina Basin, Northern Territory, Australia.He identified potential source areas and discussed the application ofrutile dating to diamond exploration.

4.4.3. Pb diffusionThe closure temperature for U in rutile is strongly dependent on

grain size (Mezger et al., 1991; Cherniak, 2000; see equation below).Thus, if rutile grains of different sizes are dated, as is commonly thecase in sedimentary provenance studies, different rutile ages may notnecessarily represent different igneous or metamorphic events, butmay reflect the cooling history of each individual rutile grain.However, the differences between closure temperatures for rutilegrains of different sizes are only of minor significance (few tens ofdegrees for cooling rates between 1 and 10 °C Ma−1 and grain sizesup to a few millimetres) (Cherniak, 2000). The correspondingmathematical expression to determine the closure temperature (Tc)of rutile, as applied to any other mineral, is given as:

Tc =E = R

ln A × R × T2c × D0 = a

2� �= E × CrÞ

�

where R is the gas constant, E the activation energy, A the geometricfactor, D the factor for diffusion of the relevant species, a the effectivediffusion radius and Cr the cooling rate (Dodson, 1973). Cherniak (2000)gave examples of closure temperature values of 567 °C for 70 μm-sizegrains and 617 °C for 200 μm-size grains, for a cooling rate of 1 °C Ma−1

with grains of spherical geometry.Moreover, it is likely that under someconditions of slow cooling, rutile will record significantly younger U–Pbages compared to coexisting zircon (Cherniak, 2000). Li et al. (2003)pointed out that a number of field-based studies on rutile of slowlycooled terrains have demonstrated younger U–Pb ages compared withcoexisting titanite and hornblende Ar–Ar ages (Mezger et al., 1989;Bibikova et al., 2001; Hirdes and Davis, 2002; Schmitz and Bowring,2003). Although the causes of the disagreement between the experi-mental Pb diffusion data and the field-based observations remainedunclear, Li et al. (2003) expressed their preference for the field-basedrutile closure temperature estimates by Mezger et al. (1989).

Kramers et al. (2009) recently discussed the valence state of Pb inzircon and suggested that radiogenic Pb is tetravalent, being similar inionic charge and effective ionic radius to U and Th, and hence has anextremely low diffusivity. In general, the loss of radiogenic Pb causesyounger U–Pb ages. However, “radiogenic Pb cannot be lost from zirconcrystals exceptbybeing reduced to thedivalent state” that canbecaused

by hydrothermal fluids and natural leaching by groundwater, “afterwhich it would become both incompatible in the lattice and highlymobile in solution” (Kramers et al., 2009). Although data are stillpending, it is likely that in rutile radiogenic Pb is also tetravalent. Inconclusion, fluids aremore likely to affect rutile in slowly cooled than inrapidly cooled terrains. The change from tetravalent to divalent Pbcauses loss of radiogenic Pb and thus of “age” (Kramers et al., 2009). Thismay explain why rutile from slowly cooled terrains often has youngerU–Pb ages compared with coexisting titanite and hornblende Ar–Arages. The disagreement between the experimental Pb diffusion data andthe field-based observations may be because the experiments do notfully reflect the conditions for slowly cooled terrains andhence a changeof the valence state of radiogenic Pb does not occur in the experiments.

4.5. (U–Th)/He thermochronology

4.5.1. IntroductionThe application of (U–Th)/He thermochronology to rutile is still in

its preliminary stages. In general, thermochronology is a temperature-sensitive radiometric dating technique, which constrains low-tem-perature, upper crustal processes such as timing and duration ofmineralisation, rate of exhumation and erosion of igneous andmetamorphic rocks (Farley, 2002; McInnes et al., 2005; Reiners andBrandon, 2006, and references therein). The method is based on themeasurement of radiogenic 4He produced from 238U, 235U and 232Thdecay (Farley, 2002; Reiners and Brandon, 2006; Table 4). Thedaughter helium is retained in the rutile crystal lattice until the grainis heated above the closure temperature where the lattice becomesweak for helium loss. Preliminary (U–Th)/He thermochronology onrutile by Crowhurst et al. (2002) has suggested a closure temperatureof N180–200 °C, which is about 100 °C higher than the closuretemperature for apatite (75–100 °C; Farley, 2002) but in the range ofthe closure temperature for zircon (171–196 °C; Reiners et al., 2004).Initial step-heating He diffusion experiments by Stockli et al. (2005,2007) and Wolfe et al. (2007) suggest a closure temperature of about220–235 °C. As already documented in the previous section, theclosure temperature is dependent on a series of parameters such asgrain size, shape and cooling rate. In the case of rapid cooling of thesample, the (U–Th)/He age reflects cooling of the sample through itsclosure temperature and can often be related to a particular geologicalevent (Dodson, 1973;McInnes et al., 2005). Slow cooling over a longertime interval, however, will give an age that is not necessarily relatedto any specific geological event (McInnes et al., 2005). Further detailsabout the dependence of closure temperature from cooling rate can befound, for instance, in Reiners and Brandon (2006).

4.5.2. ExamplesOnly a few applications of (U–Th)/He thermochronology to rutile

have been published. Crowhurst et al. (2002) analysed rutile from ametamorphic rock in South Australia and determined an average (U–Th)/He age of 472±20 Ma that they interpreted as later stage coolingrelated to the Delamerian Orogeny. McInnes et al. (2005) presentedpreliminary rutile and zircon age data of a porphyry copper depositfrom Iran, which yielded identical ages within error supporting thepredicted similarity in rutile and zircon He closure temperatures.Stockli et al. (2007) analysed rutile from mantle and lower crustalxenoliths from Cenozoic volcanic rocks in the western U.S.A. anddemonstrated that the determined (U–Th)/He ages are in excellentagreementwith both 40Ar/39Ar and zircon (U–Th)/He data. To quantifythe position of the rutile He partial retention zone (e.g. Reiners andBrandon, 2006) and to constrain the thermal history of Variscanbasement rocks,Wolfe et al. (2007) determined rutile (U–Th)/He agesof amphibolites from the borehole of German Continental DeepDrilling Project,which is, at 9101 mand a cost of aboutUS$350 million,the deepest and most expensive borehole for research in Germany(Emmermann and Lauterjung, 1997). Dunkl and von Eynatten (2009)

Fig. 23. Schematic diagram for thermal history of specific minerals in an idealised rockduring uplift. The temperature represents the closure temperature for each radiometricsystem of the individual mineral. The closure temperatures were taken from Cherniak(2000), Möller et al. (2000) and Crowhurst et al. (2002).

Fig. 24. Box and whisker plots showing Hf values for rutile from different sourcelithologies. The box represents the middle 50%; the bar inside the box represents themedian. ‘Outliers’ are represented by black rectangles. n — number of data used. SeeTable 5 for references.


used anchizonal–hydrothermal grown rutile crystals from the sub-greenschist facies metamorphosed Mesozoic sandstones of Oman for(U–Th)/He thermochronology,which allowed them to determine fluidand thermal events after Late Cretaceous ophiolite emplacement.

Although the results outlined above are preliminary studies only, itseems obvious that (U–Th)/He thermochronology on rutile can placeimportant constraints on the igneous and metamorphic evolution of aregion. Moreover, as already applied for zircon (McInnes et al., 2005,and references therein), combined U–Pb dating and (U–Th)/Hethermochronology on rutile grains can provide information on theirage of formation and cooling history (Fig. 23). Note at the time ofwriting this paper no study had been published about (U–Th)/Hethermochronology on detrital rutile. Nonetheless, this might changein the future since (U–Th)/He thermochronology seems useful insediment provenance analysis to reconstruct both the age of potentialsource lithologies and the timing of tectonic uplift in the source area.

4.6. Lu–Hf isotopes

4.6.1. IntroductionRutile typically has Hf concentrations between b5 and 120 ppm,

but also higher amounts occur (Table 5; Fig. 24), and low Lu/Hf ratios,so that correction for in situ radiogenic growth is negligible. Hafniumisotope studies of single minerals are based on the occurrences of the

Table 5Hf values (in ppm) for rutile from different source lithologies compiled from literature.Note that the lowermost concentrations for Hf (minimum values) are defined by thedetection limit of the technique applied for analysis. Felsic granulite comprises heregranulite facies gneiss. Quartz vein data are mainly from eclogite facies quartz veins(n=74), supplemented by a single low-temperature (hydrothermal) quartz veinsample (n=1).

Felsic granulite Eclogite Quartz vein Metasediment

n 173 368 75 19Min 0.05 1.65 1.34 1.08Max 194 189 86 21Med 68 12 9 4Avg 76 12 10 6Std 43 11 9 5Ref (1) (2) (3) (4)

Abbreviations: n — number of data, Min — minimum value, Max — maximum value,Med—Median, Avg— average (arithmetic mean), Std— Standard deviation (1σ). Ref—References: (1) Luvizotto and Zack (2009); (2) Zack et al. (2002), Xiao et al. (2006), Gaoet al. (2007), Miller et al. (2007), Schmidt et al. (2009); (3) Zack et al. (2002), Xiao et al.(2006), Gao et al. (2007), John et al. (2008); (4) Zack et al. (2002), Luvizotto et al.(2009a).

unstable (radioactive) 176Lu isotope incorporated into the crystallattice, which undergoes spontaneous β-decay to the stable daughter176Hf isotope, with a decay constant of 1.93×10−11 year−1 (Sguignaet al., 1982). The decay constant of 176Lu, however, has currently beenunder review, which led to proposals of revised decay constants, i.e.1.865×10−11 year−1 (Scherer et al., 2001), 1.983×10−11 year−1

(Bizzarro et al., 2003) and 1.945×10−11 year−1 (Luo and Kong,2006). Owing to the large half-life of 176Lu of about 35–40 billionyears, the Lu–Hf system is suitable for tracing the history of the solarsystem and the evolution of the Earth's crust–mantle system (Patchettet al., 1981; Patchett, 1983; Salters and Zindler, 1995; Blichert-Toftand Albarède, 1997; Amelin et al., 1999; Griffin et al., 2000;Choukroun et al., 2005; Amelin, 2006; Aulbach et al., 2008).

The Lu–Hf isotope system is generally less disturbed by alterationprocesses than other isotope systems such as Rb–Sr, Sm–Nd and U–Pb(see discussions in Patchett, 1983; Griffin et al., 2000; Kinny andMaas,2003). Experimental studies have shown that Hf diffusion issignificantly slower than diffusion of divalent and trivalent cationsubstitutions; for example, it is about an order of magnitude slowerthan Pb diffusion (Cherniak et al., 2007b). However, Luvizotto andZack (2009) have recently shown for granulite faciesmetapelitic rocksfrom the Ivrea–Verbano Zone that Hf incorporation in rutile is tem-perature dependent.

The Lu–Hf isotope system has been widely applied in earth sciencesover the last decades. Its application is based on the fact that Lu and Hfpartition differently into specific minerals such as garnet, zircon andrutile, and Lu/Hf ratios are thereby strongly fractionated during partialmelting, metamorphism andmetasomatism (Salters and Zindler, 1995;Amelin et al., 1999; Griffin et al., 2000; Kinny and Maas, 2003).Therefore, the Hf isotope composition of the Earth's crust–mantlesystem varies widely between the depletedmantle (Lu/HfNchondritic),the enriched crust (Lu/Hfbchondritic) and any remaining unfractio-nated source (Lu/Hf=chondritic), as shown in Fig. 25. Different Lu/Hfratios reflect the long-term evolution of these reservoirs (Patchett et al.,1981; Choukroun et al., 2005). Hafnium preferentially enters the meltphase, which leaves a residuum with relatively higher Lu/Hf ratios forthe subcontinental lithospheric mantle. However, metasomatism bymelts derived from the asthenospheric mantle can introduce Hf, whichproduces lithospheric mantle with relatively low Lu/Hf ratios (Chouk-ukroun et al., 2005). The deviations of the Hf isotope composition of a

image of Fig.�23

image of Fig.�24

Fig. 25. (a) Schematic illustration of Lu–Hf isotope evolution in the Earth's crust–mantlesystem (modified from Patchett et al., 1981; Kinny and Maas, 2003). Partial melting inthe Earth's mantle at time t1 results in divergent Hf isotope evolution paths for thenewly generated crust (low Lu/Hf) and the residual mantle (high Lu/Hf). This is becauseHf enters the melt phase and Lu is preferentially retained in the mantle, which becomesmore radiogenic with time. Hence, any rutile formed within the crust has extremelylow Lu/Hf, which over time diverges in composition from the remainder of the hostrock. At time t2, a variety of possible sources may contribute to newly formed crust.(b) Schematic illustration showing εHf as function of crystallisation age. The 176Hf/177Hfratio and the εHf value of a sample (calculated for the age of the sample) can be used toproduce a growth line that indicates the depleted mantle curve. The intersection yieldsa depleted mantle (TDM) model age. This model age could reflect the time (t1) at whichthe source of the magma from which a mineral (e.g. rutile) crystallised was extractedfrom the depleted mantle reservoir. Alternatively, the model age may reflect a mixingage of more ancient (e.g. with TDM model age of t1) with more juvenile (with a TDMmodel age of t3) crust.


sample from that of the chondritic uniform reservoir (CHUR) are com-monly expressed in epsilon units (εHf) as given by following equation(Patchett et al., 1981):

εHf =

176Hf =177Hf� �

sample176Hf =177Hf� �

chondrite

−1

264

375 × 104

Samples with higher than chondritic 176Hf/177Hf at time t havepositive εHf values; those with lower than chondritic 176Hf/177Hf havenegative εHf values, and hence chondrites per definition have εHf=0.The 176Hf/177Hf ratios are used to determine Hf model ages, which area measure of the average time since the source of the magma fromwhich a mineral (e.g. rutile) crystallised was extracted from thedepleted mantle reservoir (Fig. 25b).

4.6.2. ExamplesThe use of in situ Lu–Hf isotope analysis has rapidly increased in

recent years because of an increase in sophisticated laser ablationmulti-collector ICP-MS facilities, which allow precise isotope analysisof samples with Hf quantities as low as 25 ng (Blichert-Toft andAlbarède, 1997; Amelin et al., 1999). Choukroun et al. (2005) analysedthe Hf isotope composition of rutile from MARID xenoliths of theKimberley area, South Africa. The 176Hf/177Hf ratios are highly variable(0.2811–0.2858, εHf=−55 to +110), with much of this range foundin single samples and even within single grains. They noted that sucha wide range of Hf isotope composition within single samples andwithin single rutile grains could not be generated by radioactive decayof 176Lu in the rutile within the age of the Earth. Choukroun et al.(2005) therefore interpreted the ranges in Hf isotope composition asreflecting primary interaction of an asthenospheric-derived melt withancient depleted harzburgitic mantle, which was later overprinted bymetasomatism. The authors explained low 176Hf/177Hf ratios stillpreserved in some MARID rutile grains by mixing between anasthenospheric-derived melt and the ancient subcontinental litho-spheric mantle.

Aulbach et al. (2008) analysed 176Hf/177Hf of rutile in eclogitexenoliths from kimberlites of the Lac de Gras area, northern Canada.They received similar, highly variable 176Hf/177Hf ratios (0.28156–0.28568, εHf=−43 to +103), with negligible intergrowth ofradiogenic Hf in rutile since emplacement of the kimberlite, asshown by low 176Lu/177Hf ratio of 0.000039±0.000077 (1σ). Theyrecognised a correlation between Nb/Ta and minimum 176Hf/177Hf ofeclogitic rutiles, and interpreted the low 176Hf/177Hf and suprachon-dritic Nb/Ta values as acquired during interaction with a componentderived from ancient metasomatised subcontinental lithosphericmantle. By contrast, they interpreted rutile with high 176Hf/177Hfand subchondritic Nb/Ta values as having preserved its primary HFSEconcentrations and isotope characteristics. Their study clearly showsthat Lu–Hf isotope analysis combinedwith trace element geochemicaldata of rutile is particularly helpful for a better understanding of theevolution of the Earth's crust and mantle. New studies are under wayto improve Lu–Hf isotope analysis on rutile (Ewing et al., 2009).

At the time of writing this paper, no study had been publishedabout Lu–Hf isotope analysis of detrital rutile. However, this mightchange in the future since the Lu–Hf isotope composition of rutilerepresents an estimate of the protolith composition at the time ofcrystallisation and therefore is helpful in tracing potential sourcerocks in sediment provenance studies.

5. Economic importance of rutile

5.1. Introduction

Although the primary purpose of this paper is to provideinformation on various applications of rutile in earth sciences, anoutline of the economic importance of rutile is essential because theacademic issues mentioned above have also important commercialimplications.

One of the major subjects for earth scientists is the exploration andevaluation of mineral raw materials, including hydrocarbons, gold,diamonds, chromium, iron, nickel and platinum groupmetals but alsotitanium minerals. The world total rutile reserves are estimated tobe 45 million t and those of ilmenite are about 680 million t, withilmenite supplying about 92% of the world's demand for titaniumminerals (Gambogi, 2009). Titanium minerals are commerciallyimportant because they are processed to titanium metal, which isused, for instance, in the aerospace industry because of its lowweight,high strength and resistance to heat and corrosion. Rutile is one of thefavoured minerals for the production of titanium dioxide whitepigment, dominantly through the chloride manufacturing process(Stanaway, 1994; Korneliussen et al., 2000). The main applications of

image of Fig.�25

Table 6Key elements in natural rutile useful for a wide range of applications in earth sciences(see text for explanation).

Key elements Applications Comment

Cr and Nb Source rockcharacterisation

These elements allow discriminationbetween rutile derived from metamafic


titanium dioxide white pigment are in the manufacture of paint (51%of total production), paper (19%) and plastics (17%) (Pearson, 1999;Carp et al., 2004; Gambogi, 2008). Other uses include ceramics, coatedfabrics and textiles, floor coverings, printing ink, roofing granules,food colouring (E171), tablet coating, toothpaste and as a UV absorberin sunscreen creamwith high sun protection factors (Carp et al., 2004;Gambogi, 2008, and references therein). Thus, titanium dioxide(rutile) is always present in our daily life. Moreover, since Fujishimaand Honda (1972) successfully showed the application of TiO2 as aphotoanode to decompose water by visible light, anatase has receivedmuch attention in photocatalysis (Carp et al., 2004). This use has alsobeen extended to rutile (e.g. Lu et al., 2004; Chuan et al., 2008),although its reaction rate is a fifth of anatase (Chuan et al., 2008). Incontrast to rutile containing, for example, V and Fe, pure rutile showsno photoactivity (Lu et al., 2004). Chuan et al. (2008) used natural V-bearing rutile from a rutile mine in the Shaanxi Province, China, todecompose methylene blue and suggested the application of rutile forlarge-scale photocatalytic decomposition of organic pollutants inquiet and still waters.

5.2. Economic importance

Most of the natural rutile used in industry comes fromheavymineralsands (placer deposits) enriched in ilmenite and rutile (e.g. Force, 1991;Roy, 1999; Pirkle et al., 2007). The world's largest sedimentary depositsof rutile and the largest rutile mine are both in Sierra Leone. Before itsclosure in 1995, the rutile operation in Sierra Leone supplied 137,000 t(Mobbs, 1996), whichwas about two-thirds of theworld's rutile outputin 1994. Although rutile is commercially important, rutilemining causesdrastic changes to the environment (Akiwumi and Butler, 2008). TheSierra Rutile Mine reopened in 2006, and Sierra Leonemay become oneof the world's leading rutile producers in the future. In 2006, 70,360 t ofrutile (worth US$28.5 million) was exported (Bermúdez-Lugo, 2008).Other African rutile placer deposits occur in Cameroon (exploitedbetween 1935 and 1955 near Yaoundé), Gambia (mined in the 1950s),Guinea (deposits not yet exploited), Kenya (to commence in the nearfuture), Malawi (exploration has been conducted in recent years) andSouth Africa (Stendal et al., 2006; Dill, 2007b; Schlüter, 2008). Rutileplacer deposits are also mined in Australia, India, Ceylon and U.S.A.(Goldsmith and Force, 1978; Force, 1991; Roy, 1999; Force, 2000; Pirkleet al., 2007).

Fig. 26 shows the world largest producers of natural rutile and thetrend of growth between 2006 and 2008. For example, in 2008, theworld production of natural rutile was about 608,000 t, with Australia(309,000 t), South Africa (121,000 t) and Sierra Leone (95,000 t)being the three largest producers (Gambogi, 2009). However, rutileplacer deposits are limited in volume and are rapidly being depleted,and therefore, the current producers may not be able to fulfil theworld's need in the future (Korneliussen, 1980; Korneliussen et al.,

Fig. 26. World production of natural rutile by country between 2006 and 2008,according to data in Gambogi (2008, 2009).

2000), with Sierra Leone being an exception. Thus, an alternativesource for high-grade TiO2 ores (such as eclogite) has to be found.

The eclogites of the Western Gneiss Region, Norway, containseveral million tons of rutile, and are therefore a large rutile resource(Korneliussen and Foslie, 1985; Korneliussen et al., 2000). Theeclogites occur as pods and lenses within amphibolite to granulitefacies metamorphosed Proterozoic/sub-Caledonian gneisses and haverutile concentrations in the range of 1 to 4 wt.%, although higherconcentrations occur locally (Korneliussen, 1980; Korneliussen andFoslie, 1985). Ilmenite is important in the economic evaluation ofrutile-rich eclogite deposits, for two main reasons (Korneliussen andFoslie, 1985). First, intergrowths of less-valuable ilmenite will lowerthe purity, and accordingly the values of the rutile concentrate that canbe produced. Second, an increase in the ilmenite concentration ineclogitewill lead to a correspondingly smaller amount of Ti available toform rutile (Korneliussen and Foslie, 1985).Moreover, the grain size ofthe rutile and the CaO content in the concentrates (should be less than0.2%) are of considerable importance in the economic evaluation ofrutile-rich eclogite deposits (Korneliussen et al., 2000). Furtherexamples of rutile-bearing eclogite of economic importance areknown from the Piampaludo deposit, Italy (Force, 1991; Liou et al.,1998), the Shubino deposit, Russia (Force, 1991) and from the Dabie–Sulu deposits, China (Chen et al., 2005; Huang et al., 2006; Zhang et al.,2006). For instance, in the Sulu UHP metamorphic terrane the rutilemodal content in eclogite is 2–5 vol.% and can be as high as 8–10 vol.%(Chen et al., 2005).

Minor economically important sources of natural rutile are oredeposits (Czamanske et al., 1981; Clark and Williams-Jones, 2004),amphibolitic rocks (Korneliussen et al., 2000: 40), granitic pegmatitesand rare-earth elementmineralisation (Scott, 1988; Černý et al., 1999;Černý and Chapman, 2001). Clark and Williams-Jones (2004)discussed anomalous compositions of rutile at certain deposits fortheir potential as indicators of metallic mineralisation (see Scott,1988, 2005; Scott and Radford, 2007). Thus, detrital rutile can be usedas pathfinder mineral in stream sediments to guide the explorationgeologists to metallic mineralisation. Table 2 shows a compilation ofvarious rutile-bearing deposits and the characteristic trace elementsincorporated into the rutile crystal lattice. Moreover, besides pyropegarnet, chrome diopside and chrome spinel, rutile can also be used asa kimberlite indicator mineral (Smythe et al., 2008) and thereforeplays an important role in diamond exploration.

lithologies (high Cr, low Nb) or metapeliticlithologies (low Cr, high Nb).

V, Ni, Cu, Nb, Sn,Sb, Ta and W

Source rockcharacterisation

Rutile containing these elements is useful aspathfinder mineral in stream sediments toidentify and trace the type of metallicmineralisation.

Zr Zr-in-rutilethermometry

Zr in rutile can yield the temperature ofrutile crystallisation.

O O isotopy O isotope data can yield information aboutthe temperature of rutile crystallisation andthe extent and nature of fluid–mineralinteractions.

U and Pb U–Pbgeochronology

U/Pb and Pb/Pb isotope ratios can yield theage of rutile crystallisation.

U, Th and He (U–Th)/Hethermochronology

(U–Th)/He isotope ratios are used tocalculate an age related to the time therutile cooled through about 200 °C.

Lu and Hf Lu–Hf isotopy The Hf isotope composition of rutile allowsidentifying the magmatic source byreference to an Earth model.

image of Fig.�26


6. Summary

Rutile is widely distributed as an accessory mineral in igneous,metamorphic and sedimentary rocks. Its geochemical compositionallows tracing the formation and evolution of the Earth's continentalcrust because rutile is a major host mineral for Nb, Ta and other HFSE,which are widely used as a monitor of geochemical processes in thecrust and mantle such as magma evolution and subduction-zonemetamorphism. Processes influencing the Nb/Ta ratio of minerals (e.g.rutile) and rocks are continuously topics of scientific debate. In recentyears, many data have been generated which significantly increasedour knowledge about rutile and its host lithologies. Table 6 gives asummary of key elements in natural rutile that are useful for a widerange of applications in earth sciences. For example, elements such asCr, Nb, Sb andWare used to trace the provenance of rutile. A number ofpublications have already shown that rutile geochemistry, Zr-in-rutilethermometry and isotope studies of rutile are useful methods in bothhard and soft rock geology. Rutile is also of economic importancebecause of its use in the manufacture of white titanium dioxidepigment, which is a major constituent in various products of our dailylife. Heavy mineral sands containing a significant percentage of rutileare therefore the focus of exploration worldwide. Because thesemineral sands are limited in volume and are rapidly being depleted, analternative source for high-grade TiO2 ores has to be found. This clearlyshows the growing demand for further rutile-related research in earthsciences. I hope that this reviewwill serve as a good source of referencefor earth scientists both in academic research and in industry.

Acknowledgements

I would like to thank all the scientists who have been interested innatural rutile in the last years producing helpful data used in this paper.Thanks go also to everyone who provided me with literature. ArzuArslan and Hong Tan made helpful suggestions during the preparationof the manuscript. Robert Scott improved the English style andgrammar of the manuscript. Thanks go also to Sally Gibson and DirkFrei for reading Sections 4.1.3 and 4.4. respectively. The thin sectionphotomicrographs of rutile-bearing rocks have been reproduced withpermission of the Sedgwick Museum of Earth Sciences, University ofCambridge. Finally, I am grateful to Maria Mange and Andrew Mortonfor their helpful comments on a previous version of the manuscript.

References

Addy, S.K., Garlick, G.D., 1974. Oxygen isotope fractionation between rutile and water.Contributions to Mineralogy and Petrology 45, 119–121.

Agrinier, P., 1991. The natural calibration of 18O/16O geothermometers: application tothe quartz–rutile mineral pair. Chemical Geology 91, 49–64.

Agrinier, P., Javoy, M., Smith, D.C., Pineau, F., 1985. Carbon and oxygen isotopes ineclogites, amphibolites, veins and marbles from the Western Gneiss Region,Norway. Chemical Geology 52, 145–162.

Akdogan, N., Rameev, B.Z., Khaibullin, R.I., Westphalen, A., Tagirov, L.R., Aktaş, B., Zabel,H., 2006. Anisotropic ferromagnetism in Co-implanted TiO2 rutile. Journal ofMagnetism and Magnetic Materials 300, e4–e7.

Akiwumi, F.A., Butler, D.R., 2008. Mining and environmental change in Sierra Leone,West Africa: a remote sensing and hydrogeomorphological study. EnvironmentalMonitoring and Assessment 142, 309–318.

Allen, C.M., Campbell, I.H., 2007. Spot dating of detrital rutile by LA-Q-ICP-MS: apowerful provenance tool. GSA Denver Annual Meeting, 28–31 October 2007,Abstract, Paper, no. 196-12.

Amelin, Y., 2006. Meteorite phosphates show constant 176Lu decay rate since4557 million years ago. Science 310, 839–841.

Amelin, Y., Lee, D.-C., Halliday, A.N., Pidgeon, R.T., 1999. Nature of the Earth's earliestcrust from hafnium isotopes in single detrital zircons. Nature 399, 252–255.

Andersen, T., 2002. Correction of common lead in U–Pb analyses that do not report204Pb. Chemical Geology 192, 59–79.

Anderson, A.L., 1960. Genetic aspects of the monazite and columbium-bearing rutiledeposits in northern Lemhi county, Idaho. Economic Geology 55, 1179–1201.

Attoh, K., Nude, P.M., 2008. Tectonic significance of carbonatite and ultrahigh-pressurerocks in the Pan-African Dahomeyide suture zone, southeastern Ghana. In: Ennih,N., Liégeois, J.-P. (Eds.), The Boundaries of the West African Craton: GeologicalSociety of London, Special Publication, vol. 297, pp. 217–231.

Aulbach, S., O'Reilly, S.Y., Griffin, W.L., Pearson, N.J., 2008. Subcontinental lithosphericmantle origin of high niobium/tantalum ratios in eclogites. Nature Geoscience 1,468–472.

Baier, J., Audétat, A., Keppler, H., 2008. The origin of the negative niobium tantalumanomaly in subduction zone magmas. Earth and Planetary Science Letters 267,290–300.

Bailey, D.K., 1961. Intrusive limestones in the Keshya and Mkwisi valleys, NorthernRhodesia. Quarterly Journal of the Geological Society 117, 419–442.

Bakun-Czubarow, N., Kusy, D., Fiala, J., 2005. Trace element abundances in rutile fromeclogite–granulite rock series of the Złote mountains in the Sudetes. MineralogicalSociety of Poland, Special Papers 26, 132–136.

Baldwin, J.A., Brown, M., 2008. Age and duration of ultrahigh-temperature metamor-phism in the Anapolis–Itaucu Complex, Southern Brasilia Belt, central Brazil —

constraints from U–Pb geochronology, mineral rare earth element chemistry andtrace-element thermometry. Journal of Metamorphic Geology 26, 213–233.

Baldwin, S.L., Monteleone, B.D., Webb, L.E., Fitzgerald, P.G., Grove, M., Hill, J., 2004.Pliocene eclogite exhumation at plate tectonic rates in eastern Papua New Guinea.Nature 431, 263–267.

Banfield, J.F., Veblen, D.R., 1991. The structure and origin of Fe-bearing platelets inmetamorphic rutile. American Mineralogist 76, 113–127.

Baur, W.H., 1956. Über die Verfeinerung der Kristallstrukturbestimmung einigerVertreter des Rutiletyps: TiO2, SnO2, GeO2 und MgF2. Acta Crystallographica 9,515–520.

Baur, W.H., 1961. Atomabstände und Bindungswinkel im Brookit, TiO2. Acta Crystal-lographica 14, 214–216.

Baur, W.H., 2007. The rutile type and its derivatives. Crystallography Reviews 13,65–113.

Bayley, W.S., 1923. The occurrence of rutile in the titaniferous magnetites of westernNorth Carolina and eastern Tennessee. Economic Geology 18, 382–392.

Bell, D., Rossman, G., 1992. Water in Earth's mantle: the role of nominally anhydrousminerals. Science 255, 1391–1397.

Bermúdez-Lugo, O., 2008. The mineral industries of Liberia and Sierra Leone. 2006Minerals Yearbook. U.S. Geological Survey.

Bibikova, E., Skiold, T., Bogdanova, S., Gorbatschev, R., Slabunov, A., 2001. Titanite–rutilethermochronometry across the boundary between the Archaean Craton in Kareliaand the Belomorian Mobile Belt, eastern Baltic Shield. Precambrian Research 105,315–330.

Birch, W.D., Barron, L.M., Magee, C., Sutherland, F.L., 2007. Gold- and diamond-bearingWhite Hills Gravel, St Arnaud district, Victoria: age and provenance based on U–Pbdating of zircon and rutile. Australian Journal of Earth Sciences 54, 609–628.

Bizzarro, M., Baker, J.A., Haack, H., Ulfbeck, D., Rosing, M., 2003. Early history of theEarth's crust–mantle system inferred from hafnium isotopes in chondrites. Nature421, 931–933.

Blichert-Toft, J., Albarède, F., 1997. The Lu–Hf isotope geochemistry of chondrites andthe evolution of the mantle–crust system. Earth and Planetary Science Letters 148,243–258.

Boswell, P.G.H., 1933. On the Mineralogy of Sedimentary Rocks. A Series of Essays and aBibliography. Thomas Murby & Company, London. 393 pp.

Bramdeo, S., Dunlevey, J.N., 2000. Geochemistry of detrital rutile. In: Kisters, A.F.M.,Thomas, R.J. (Eds.), Geocongress 2000: A New Millennium on Ancient Crust, 27thEarth Science Congress of the Geological Society of South Africa: Journal of AfricanEarth Sciences, vol. 31, pp. 8–9.

Brenan, J.M., Shaw, H.F., Phinney, D.L., Ryerson, F.J., 1994. Rutile–aqueous fluidpartitioning of Nb, Ta, Hf, Zr, U and Th: implications for high field strength elementdepletions in island-arc basalts. Earth and Planetary Science Letters 128, 327–339.

Bromiley, G.D., Hilairet, N., 2005. Hydrogen and minor element incorporation insynthetic rutile. Mineralogical Magazine 69, 345–358.

Bromiley, G.D., Redfern, S.A.T., 2008. The role of TiO2 phases during melting ofsubduction-modified crust: implications for deep mantle melting. Earth andPlanetary Science Letters 267, 301–308.

Bromiley, G.D., Hilairet, N., McCammon, C., 2004. Solubility of hydrogen and ferric ironin rutile and TiO2 (II): implications for phase assemblages during ultrahigh-pressure metamorphism and for the stability of silica polymorphs in the lowermantle. Geophysical Research Letters 31, LO4610.

Buddington, A.F., Lindsley, D.H., 1964. Iron–titanium oxide minerals and syntheticequivalents. Journal of Petrology 5, 310–357.

Buist, D.S., 1963a. The determination of the rutile content of beach sands from Moana,South Australia, using the Frantz isodynamic separator. Journal of SedimentaryResearch 33, 799–801.

Buist, D.S., 1963b. The Geiger counter X-ray diffractometer for determining the rutilecontent of heavy mineral separations of beach sands. Journal of SedimentaryResearch 33, 945–947.

Buseck, P.R., Keil, K., 1966. Meteoritic rutile. American Mineralogist 51, 1506–1515.Carp, O., Huisman, C.L., Reller, A., 2004. Photoinduced reactivity of titanium dioxide.

Progress in Solid State Chemistry 32, 33–177.Carruzzo, S., Clarke, D.B., Pelrine, K.M., MacDonald, M.A., 2006. Texture, composition,

and origin of rutile in the South Mountain Batholith, Nova Scotia. CanadianMineralogist 44, 715–729.

Černý, P., Chapman, R., 2001. Exsolution and breakdown of scandian and tungstenianNb–Ta–Ti–Fe–Mn phases in niobian rutile. Canadian Mineralogist 39, 93–101.

Černý, P., Čech, F., Povondra, P., 1964. Review of ilmenorutile–struvertite minerals.Neues Jahrbuch für Mineralogie Abhandlungen 101, 142–172.

Černý, P., Chapman, R., Göd, R., Niedermayr, G., Wise, M.A., 1989. Exsolutionintergrowth of titanian ferrocolumbite and niobian rutile from the Weinebenespodumene pegmatites, Carinthia, Austria. Mineralogy and Petrology 40,197–206.


Černý, P., Chapman, R., Simmons, W.B., Chackowsky, L.E., 1999. Niobian rutile from theMcGuire granitic pegmatite, Park County, Colorado; solid solution, exsolution, andoxidation. American Mineralogist 84, 754–763.

Černý, P., Novák, M., Chapman, R., Ferreira, K.J., 2007. Subsolidus behavior ofniobian rutile from the Písek region, Czech Republic: a model for exsolution inW- and Fe2+≫Fe3+-rich phases. Journal of Geosciences 52, 143–159.

Chacko, T., Hu, X., Mayeda, T.K., Clayton, R.N., Goldsmith, J.R., 1996. Oxygen isotopefractionations in muscovite, phlogopite, and rutile. Geochimica et CosmochimicaActa 60, 2595–2608.

Chao, E.C.T., Fahey, J.J., Littler, J.,Milton, D.J., 1962. Stishovite, SiO2, a very high pressure newmineral from Meteor Crater, Arizona. Journal of Geophysical Research 67, 419–421.

Chen, Z.Y., Li, Q.L., 2008. Zr-in-rutile thermometry in eclogite at Jinheqiao in the Dabieorogen and its geochemical implications. Chinese Science Bulletin 53, 768–776.

Chen, Z.Y., Yuchuan, C., Denghong, W., Jue, X., Jianxiong, Z., 2005. Rutiles in eclogitefrom the Sulu UHPM Terrane: a preliminary study. In: Mao, J., Bierlein, F.P. (Eds.),Mineral Deposit Research: Meeting the Global Challenge, pp. 731–733.

Chen, Z.Y., Wang, D.H., Chen, Y.C., Xu, J., Yu, J.J., Wang, P.A., 2006. Mineral geochemistryof rutile in eclogite and its implications. Earth Science— Journal of China Universityof Geosciences 31, 533–538.

Cherniak, D.J., 2000. Pb diffusion in rutile. Contribution to Mineralogy and Petrology139, 198–207.

Cherniak, D.J., Watson, E.B., Wark, D.A., 2007a. Ti diffusion in quartz. Chemical Geology236, 65–74.

Cherniak, D.J., Manchester, J., Watson, E.B., 2007b. Zr and Hf diffusion in rutile. Earthand Planetary Science Letters 261, 267–279.

Choukroun, M., O'Reilly, S.Y., Griffin, W.L., Pearson, N.J., Dawson, J.B., 2005. Hf isotopesof MARID (mica–amphibole–rutile–ilmenite–diopside) rutile trace metasomaticprocesses in the lithospheric mantle. Geology 33, 45–48.

Chuan, X.-Y., Lu, A.H., Chen, J., Li, N., Guo, Y.J., 2008. Microstructure and photocatalyticactivity of natural rutile from China for oxidation of methylene blue in water.Mineralogy and Petrology 93, 143–152.

Clark, H., 1993. Hey's Mineral Index. Mineral Species, Varieties and Synonyms3rdedition. Chapman and Hall, London. 852 pp.

Clark, J.R., Williams-Jones, A.E., 2004. Rutile as a potential indicator mineral formetamorphosed metallic ore deposits. Rapport Final de DIVEX, Sous-projet SC2,Montréal, Canada. 17 pp.

Clarke, D.B., Carruzzo, S., 2007. Assimilation of country-rock ilmenite and rutile in theSouth Mountain Batholith, Nova Scotia, Canada. Canadian Mineralogist 45, 31–42.

Corfu, F., Andrews, A.J., 1986. A U–Pb age for mineralized Nipissing diabase, Gowganda,Ontario. Canadian Journal of Earth Sciences 23, 107–109.

Corfu, F., Heaman, L.M., Rogers, G., 1994. Polymetamorphic evolution of the Lewisiancomplex, NW Scotland, as recorded by U–Pb isotopic compositions of zircon,titanite and rutile. Contributions to Mineralogy and Petrology 117, 215–228.

Cromer, D.T., Herrington, K., 1955. The structures of anatase and rutile. Journal of theAmerican Chemical Society 77, 4708–4709.

Crowhurst, P., Farley, K., Ryan, C., Duddy, I., Blacklock, K., 2002. Potential of rutile as a U–Th–He thermochronometer. Geochimica et Cosmochimica Acta 66 (Supplement 1),A158.

Czamanske, G.K., Force, E.R., Moore, W.J., 1981. Some geologic and potential resourceaspects of rutile in porphyry copper deposits. Economic Geology 76, 2240–2256.

Dawson, J.B., Smith, J.V., 1977. TheMARID (mica–amphibole–rutile–ilmenite–diopside)suite of xenoliths in kimberlite. Geochemica et Cosmochimica Acta 41, 309–323.

Deer, W.A., Howie, R.A., Zussman, J., 1992. An Introduction to Rock-Forming Minerals,2nd edition. Longman Group Ltd, Harlow, UK. 712 pp.

Desmons, J., O'Neil, J.R., 1978. Oxygen and hydrogen isotope composition of eclogitesand associated rocks from the eastern Sesia Zone (western Alps, Italy). Contribu-tions to Mineralogy and Petrology 67, 79–85.

Dewey, J.F., Mange, M.A., 1999. Petrography of Ordovician and Silurian sediments in thewestern Irish Caledonides: tracers of a short-lived Ordovician continent–arccollision orogeny and the evolution of the Laurentian Appalachian–Caledonianmargin. In: MacNiocaill, C., Ryan, P.D. (Eds.), Continental Tectonics: GeologicalSociety of London, Special Publication, vol. 164, pp. 55–107.

Dill, H.G., 2007a. Grain morphology of heavy minerals from marine and continentalplacer deposits, with special reference to Fe–Ti oxides. Sedimentary Geology 198,1–27.

Dill, H.G., 2007b. A review of mineral resources in Malawi: with special reference toaluminium variation in mineral deposits. Journal of Africa Earth Sciences 47,153–173.

Dill, H.G., Melcher, F., Füßl, M., Weber, B., 2007. The origin of rutile–ilmenite aggregates(“nigrine”) in alluvial–fluvial placers of the Hagendorf pegmatite province, NEBavaria, Germany. Mineralogy and Petrology 89, 133–158.

Dodson, M.H., 1973. Closure temperature in cooling geochronological and petrologicalsystems. Contributions to Mineralogy and Petrology 40, 259–274.

Doroshkevich, A.G., Wall, F., Ripp, G.S., 2007. Calcite-bearing dolomite carbonatitedykes from Veseloe, North Transbaikalia, Russia and possible Cr-rich mantlexenoliths. Mineralogy and Petrology 90, 19–49.

Downes, P.J., Griffin, B.J., Griffin, W.L., 2007. Mineral chemistry and zircon geochronol-ogy of xenocrysts and altered mantle and crustal xenoliths from the Ariesmicaceous kimberlite: constraints on the composition and age of the centralKimberley Craton, Western Australia. Lithos 93, 175–198.

Droop, G.T.R., 1987. A general equation for estimating Fe3+ concentrations inferromagnesian silicates and oxides frommicroprobe analyses using stoichiometriccriteria. Mineralogical Magazine 51, 431–435.

Dunkl, I., von Eynatten, H., 2009. Anchizonal–hydrothermal growth and (U–Th)/Hedating of rutile crystals in the sediments of Hawasina window, Oman. Geochimicaet Cosmochimica Acta 73 (13, Supplement 1) A314.

El Goresy, A., 1971. Meteoritic rutile: a niobium bearing mineral. Earth and PlanetaryScience Letters 11, 359–361.

El Goresy, A., 1965. Mineralbestand und Strukturen der Graphit- und Sulfideinschlüssein Eisenmeteoriten. Geochimica et Cosmochimica Acta 29, 1131–1151.

El Goresy, A., Chen, M., Gillet, P., Dubrovinsky, L., Graup, G., 2001. An natural shock-induced dense polymorph of rutile with PbO2 structure in the suevite from the RiesCrater in Germany. Earth and Planetary Science Letters 192, 485–495.

Emmermann, R., Lauterjung, J., 1997. The German Continental DeepDrilling ProgramKTB:overview and major results. Journal of Geophysical Research 102, 18179–18201.

Ewing, T.A., Rubatto, D., Eggins, S.E., 2009. In situ measurement of Hf isotopes in rutileby LA-MC-ICPMS. Geochimica et Cosmochimica Acta 73 (13, Supplement 1) A347.

Farley, K.A., 2002. U–He dating: techniques, calibrations and applications. Reviews inMineralogy & Geochemistry 47, 819–844.

Ferry, J.M., Watson, E.B., 2007. New thermodynamicmodels and revised calibrations forthe Ti-in-zircon and Zr-in-rutile thermometers. Contributions to Mineralogy andPetrology 154, 429–437.

Fett, A., 1995. Elementverteilung zwischen Granat, Klinopyroxen und Rutil in Eklogiten—

Experiment und Natur. Dissertation, University of Mainz, Germany, 227 pp.Fitches, W.R., Muir, R.J., Maltman, A.J., Bentley, M.R., 1990. Is the Colonsay–west Islay

block of SW Scotland an allochthonous terrane? Evidence from Dalradian tilliteclasts. Journal of the Geological Society 147, 417–420.

Flowers, R.M., Bowring, S.A., Tulloch, A.J., Klepeis, K.A., 2005. Tempo of burial andexhumation within the deep roots of a magmatic arc, Fiordland, New Zealand.Geology 33, 17–20.

Foley, S.F., Barth, M.G., Jenner, G.A., 2000. Rutile/melt partition coefficients for traceelements and an assessment of the influence of rutile on the trace element char-acteristics of subduction zone magmas. Geochimica et Cosmochimica Acta 64,933–938.

Foley, S., Tiepolo, M., Vannucci, R., 2002. Growth of early continental crust controlled bymelting of amphibolite in subduction zones. Nature 417, 837–840.

Force, E.R., 1980. The provenance of rutile. Journal of Sedimentary Petrology 50, 485–488.Force, E.R., 1991. Geology of titanium-mineral deposits. Geological Society of America,

Special Paper 259, 1–112.Force, E.R., 2000. Titanium mineral resources of the Western U.S.—an update. U.S.

Geological Survey, Open-File Report 00-442.Franz, L., Romer, R.L., 2007. Caledonian high-pressure metamorphism in the Strona–

Ceneri Zone (Southern Alps of southern Switzerland and northern Italy). SwissJournal of Geosciences 100, 457–467.

Franz, L., Romer, R.L., Klemd, R., Schmid, R., Oberhänsli, R., Wagner, T., Dong, S., 2001.Eclogite-facies quartz veins within metabasites of the Dabie Shan (eastern China):pressure–temperature–time–deformation path, composition of the fluid phase andfluid flow during exhumation of high-pressure rocks. Contributions to Mineralogyand Petrology 141, 322–346.

Fujishima, A., Honda, K., 1972. Electrochemical photolysis of water at a semiconductorelectrode. Nature 238, 37–38.

Gambogi, J., 2008. Titanium. 2006 Minerals Yearbook. U.S. Geological Survey.Gambogi, J., 2009. Titaniummineral concentrates. Mineral Commodity Summaries. U.S.

Geological Survey.Gao, T.-S., Wang, S.-S., Gong, B., Wu, Y.-B., Zheng, Y.-F., 2006. Postcollisional flow of

aqueous fluid within ultrahigh-pressure eclogite in the Dabie orogen. Journal ofGeochemical Exploration 89, 115–118.

Gao, J., John, T., Klemd, R., Xiong, X., 2007. Mobilization of Ti–Nb–Ta duringsubduction: evidence from rutile-bearing dehydration segregations and veinshosted in eclogite, Tianshan, NW China. Geochimica et Cosmochimica Acta 71,4974–4996.

Glodny, J., Ring, U., Kühn, A., Gleissner, P., Franz, G., 2005. Crystallization and very rapidexhumation of the youngest Alpine eclogites (Tauern Window, Eastern Alps) fromRb/Sr mineral assemblage analysis. Contributions toMineralogy and Petrology 149,699–712.

Goldsmith, R., Force, E.R., 1978. Distribution of rutile in metamorphic rocks andimplications for placer deposits. Mineralium Deposita 13, 329–343.

Gonfiantini, R., 1978. Standards for stable isotopemeasurements in natural compounds.Nature 271, 534–536.

Götze, J., 1996. Genetic information of accessory minerals in clastic sediments.Zentralblatt für Geologie und Paläontologie Teil 1 (1995), 101–118.

Graham, J., Morris, R.C., 1973. Tungsten- and antimony-substituted rutile. MineralogicalMagazine 39, 470–473.

Green, T.H., 1995. Significance of Nb/Ta as an indicator of geochemical processes in thecrust–mantle system. Chemical Geology 120, 347–359.

Grégoire, M., Bell, D.R., Le Roex, A.P., 2002. Trace element geochemistry of phlogopite-rich mafic mantle xenoliths: their classification and their relationship tophlogopite-bearing peridotites and kimberlites revisited. Contributions to Miner-alogy and Petrology 142, 603–625.

Grey, I.E., Reid, A.F., 1975. The structure of pseudorutile and its role in the naturalalteration of ilmenite. American Mineralogist 60, 898–906.

Grey, I.E., Watts, J.A., Bayliss, P., 1994. Mineralogical nomenclature: pseudorutilerevalidated and neotype given. Mineralogical Magazine 58, 597–600.

Griffin, W.L., 2008. Major transformations reveal Earth's deep secrets. Geology 36,95–96.

Griffin,W.L., Pearson, N.J., Belousova, E., Jackson, S.E., van Acheterbergh, E., O'Reilly, S.Y.,Shee, S.R., 2000. The Hf isotope composition of cratonic mantle: LAM-MC-ICPMSanalysis of zircon megacrysts in kimberlites. Geochimica et Cosmochimica Acta 64,133–147.

Guillot, S., Hattori, K.H., de Sigoyer, J., 2000. Mantle wedge serpentinization andexhumation of eclogites: insight fromeastern Ladakh, northwestHimalaya. Geology28, 199–202.


Gümbel, C.W., 1874. Die paläolithischen Eruptivgesteine des Fichtelgebirges (alsvorläufige Mittheilung). Dem Herrn Professor Dr. Franz Ritter von Kobell zur Feierseines fünfzigjährigen Doctorjubiläums, München. 50 pp.

Hacker, B.R., 1996. Eclogite formation and the rheology, buoyancy, seismicity, and H2Ocontent of oceanic crust. In: Bebout, G.E., Scholl, D.W., Kirby, S.H., Platt, J.P. (Eds.),Subduction Top to Bottom: American Geophysical Union, vol. 96, pp. 337–346.

Hammer, V.M.F., Beran, A., 1991. Variation of the OH concentration of rutiles fromdifferent geological environments. Mineralogy and Petrology 45, 1–9.

Harley, S.L., 1998.On theoccurrence and characterization of ultrahigh-temperature crustalmetamorphism. In: Treloar, P.J., O'Brien, P.J. (Eds.), What Drives Metamorphism andMetamorphic Reactions? Geological Society of London, Special Publication, vol. 138,pp. 81–107.

Harley, S.L., 2008. Refining the P–T records of UHT crustal metamorphism. Journal ofMetamorphic Geology 26, 125–154.

Harper Jr., C.L., 1996. Evidence for 92gNb in the early solar system and evaluation of anew p-process cosmochronometer from 92Nb/92Mo. Astrophysical Journal 466,437–456.

Harrison, T.M., Trail, D., Schmitt, A.K., Watson, E.B., 2007. Rutile 207Pb–206Pb ages in theJack Hills quartzite, Western Australia. Geochimica et Cosmochimica Acta 71 (15,Supplement 1) A383.

Hassan, W.F., 1994. Geochemistry and mineralogy of Ta–Nb rutile from PeninsularMalaysia. Journal of Southeast Asian Earth Sciences 10, 11–23.

Hill, E., Day, J.M.D., Davidson, J., Taylor, L.A., 2006. Petrogenesis of Apollo 17 Marebasalts — revisited. Lunar and Planetary Science XXXVII, p. 2067.

Hills, D.V., Haggerty, S.E., 1989. Petrochemistry of eclogites from the KoiduKimberlite Complex, Sierra Leone. Contribution of Mineralogy and Petrology103, 397–422.

Hirdes, W., Davis, D.W., 2002. U–Pb zircon and rutile metamorphic ages of Dahomeyangarnet-hornblende gneiss in southeastern Ghana, West Africa. Journal of AfricanEarth Sciences 35, 445–449.

Hlava, P.F., Prinz, M., Keil, K., 1972. Niobian rutile in an Apollo 14 KREEP fragment.Meteoritics 7, 479–485.

Howard, C.J., Sabine, T.M., Dickson, F., 1991. Structural and thermal parameters forrutile and anatase. Acta Crystallographica 47, 462–468.

Huang, J., Ma, D., Liu, C., Chen, H., 2006. The Xiaojiao high-grade eclogite-type rutiledeposit in Jiangsu, China: geology, geochemistry and metallogenesis. ChineseJournal of Geochemistry 25, 33–42.

Hubert, J.F., 1962. A zircon–tourmaline–rutile maturity index and the interdependenceof the composition of heavy mineral assemblages with the gross composition andtexture of sandstones. Journal of Sedimentary Petrology 32, 440–450.

Hwang, S.L., Shen, P., Chu,H.T., Yui, T.F., 2000. Nanometer-sizeα-PbO2-type TiO2 in garnet:a thermobarometer for ultrahigh-pressure metamorphism. Science 288, 321–324.

Hwang, S.L., Yui, T.F., Chu, H.T., Shen, P., Schertl, H.P., Zhang, R.Y., Liou, J.G., 2007. Onthe origin of oriented rutile needles in garnet from UHP eclogites. Journal ofMetamorphic Geology 25, 349–362.

Ireland, T.R., Williams, I.S., 2003. Considerations in zircon geochronology by SIMS. In:Hanchar, J.M., Hoskin, P.O. (Eds.), Zircon: Reviews inMineralogy and Geochemistry,vol. 53, pp. 215–241.

Jackson, J.C., Horton Jr., J.W., Chou, I-Ming, Belkin, H.E., 2006. A shock-inducedpolymorph of anatase and rutile from the Chesapeake Bay impact structure,Virginia, U.S.A. American Mineralogist 91, 604–660.

Jaffey, A.H., Flynn, K.F., Glendenin, L.E., Bentley, W.C., Essling, A.M., 1971. Precisionmeasurement of half-lives and specific activities of 235U and 238U. Physical Review C4, 1889–1906.

Janoušek, V., Krenn, E., Finger, F., Míková, J., Frýda, J., 2007. Hyperpotassic granulitesfrom Blanský les Massif (Moldanubian Zone, Bohemian Massif) revisited. Journal ofGeosciences 52, 73–112.

John, T., Klemd, R., Gao, J., Garbe-Schönberg, C.-D., 2008. Trace-element mobilization inslabs due to non steady-state fluid–rock interaction: constraints from an eclogite-facies transport vein in blueschist (Tianshan, China). Lithos 103, 1–24.

Jones, A.P., Smith, J.V., Dawson, J.B., 1982. Mantle metasomatism in 14 veinedperidotites from Bultfontein Mine, South Africa. Journal of Geology 90, 435–453.

Kalfoun, F., Ionov, D., Merlet, C., 2002. HFSE residence and Nb/Ta ratios inmetasomatised, rutile-bearing mantle peridotites. Earth and Planetary ScienceLetters 199, 49–65.

Keil, K., Bunch, T.E., Prinz, M., 1970. Mineralogy and composition of Apollo 11 lunarsamples. Proceedings of the Apollo 11 Lunar Science Conference, 1, pp. 561–598.

Khomenko, V.M., Langer, K., Rager, H., Fett, A., 1998. Electronic absorption by Ti3+ ionsand electron delocalization in synthetic blue rutile. Physics and Chemistry ofMinerals 25, 338–346.

Kimura, M., Ikeda, Y., Ebihara, M., Prinz, M., 1991. New enclaves in the Vaca Muertamesosiderite: petrogenesis and comparison with HED meteorites. Proceedings ofthe NIPR Symposium on Antarctic Meteorites 4, 263–306.

Kinny, P.D., Maas, R., 2003. Lu–Hf and Sm–Nd isotope systems in zircon. In: Hanchar, J.M., Hoskin, P.W.O. (Eds.), Zircon: Reviews in Mineralogy & Geochemistry.Mineralogical Society of America, vol. 53, pp. 327–341.

Klaproth, M.H., 1795. Beiträge zur chemischen Kenntniss der Mineralkörper, Vol. 1.Decker & Compagnie, Posen. 374 pp.

Klemme, S., Prowatke, S., Hametner, K., Günther, D., 2005. Partitioning of trace elementsbetween rutile and silicate melts: implications for subduction zones. Geochimica etCosmochimica Acta 69, 2361–2371.

Kline, S.W., 1991. Provenance of arkosic metasediments in the Virginia Blue Ridge:constraints on Appalachian suspect terrane models. American Journal of Science291, 189–198.

Korneliussen, A., 1980. Titaniferous iron and rutile deposits in Sunnfjord, westernNorway. Geologiska Föreningens i Stockholm Förhandlingar 201, 291–292.

Korneliussen, A., Foslie, G., 1985. Rutile-bearing eclogites in the Sunnfjord region ofWestern Norway. Norges Geologiske Undersøkelse Bulletin 402, 65–71.

Korneliussen, A., McLimans, R., Braathen, A., Erambert, M., Lutro, O., Ragnhildstveit, J.,2000. Rutile in eclogites as a mineral resource in the Sunnfjord region, westernNorway. Norges Geologiske Undersøkelse Bulletin 436, 39–47.

Kramers, J.D., Roddick, J.C.M., Dawson, J.B., 1983. Trace element and isotope studies onveined, metasomatic and “MARID” xenoliths from Bultfontein, South Africa. Earthand Planetary Science Letters 65, 90–106.

Kramers, J., Frei, R., Newville, M., Kober, B., Villa, I., 2009. On the valency state ofradiogenic lead in zircon and its consequences. Chemical Geology 261, 4–11.

Kretz, R., 1983. Symbols for rock-forming minerals. American Mineralogist 68,277–279.

Krogh, E.J., 1980. Geochemistry and petrology of glaucophane-bearing eclogites andassociated rocks from the Sunnfjord, Western Norway. Lithos 13, 355–380.

Krogh, E.J., 1982. Metamorphic evolution of Norwegian country-rock eclogites, asdeduced from mineral inclusions and compositional zoning in garnets. Lithos 15,305–331.

Kylander-Clark, A.R.C., Hacker, B.R., Mattinson, J.M., 2008. Slow exhumation of UHPterranes: titanite and rutile ages of the Western Gneiss Region, Norway. Earth andPlanetary Science Letters 272, 531–540.

Latroche, M., Brohan, L., Marchand, R., Tournoux, M., 1989. New hollandite oxides; TiO2

(H) and K0.06TiO2. Journal of Solid State Chemistry 81, 78–82.Li, Q., Li, S., Zheng, Y.-F., Li, H., Massonne, H.J., Wang, Q., 2003. A high precision U–Pb age of

metamorphic rutile in coesite-bearing eclogite from the Dabie Mountains in centralChina: a new constraint on the cooling history. Chemical Geology 200, 255–265.

Lindsley, D.H., 1965. Lower thermal stability of FeTi2O5–Fe2TiO5 (pseudobrookite) solidsolution series. Geological Society of America, Special Paper 87, 97.

Liou, J.G., Zhang, R., Ernst, W.G., Liu, J., McLimans, R., 1998. Mineral paragenesis in thePianpaludo eclogitis body, Gruppo di Voltri, western Ligurian Alps. SchweizerischeMineralogische und Petrographische Mitteilungen 78, 317–335.

Lu, R., Keppler, H., 1997. Water solubility in pyrope to 100 kbar. Contributions toMineralogy and Petrology 129, 35–42.

Lu, A., Liu, J., Zhao, D., Guo, Y., Li, Q., Li, N., 2004. Photocatalysis of V-bearing rutile ondegradation of halohydrocarbons. Catalysis Today 90, 337–342.

Ludwig, C.F., 1803. Handbuch der Mineralogie nach A. G. Werner. Vol. 1, SiegfriedLebrecht Crusius, Leipzig, 369 pp.

Luo, J., Kong, X., 2006. Half-life of 176Lu. Applied Radiation and Isotopes 64, 588–590.Luvizotto, G.L., Zack, T., 2009. Nb and Zr behavior in rutile during high-grade

metamorphismand retrogression: an example fromthe IvreaVerbanoZone. ChemicalGeology 261, 303–317.

Luvizotto, G.L., Zack, T., Triebold, S., von Eynatten, H., 2009a. Rutile occurrence and traceelement behavior in medium-grade metasedimentary rocks: example from theErzgebirge, Germany. Mineralogy and Petrology 97, 233–249.

Luvizotto, G.L., Zack, T., Meyer, H.P., Ludwig, T., Triebold, S., Kronz, A., Münker, C.,Stockli, D.F., Prowatke, S., Klemme, S., Jacob, D.E., von Eynatten, H., 2009b. Rutilecrystals as potential trace element and isotope mineral standards for microanalysis.Chemical Geology 261, 346–369.

MacChesney, J.N., Muan, A., 1959. Studies in the system iron oxide–titanium oxide.American Mineralogist 44, 926–945.

Mader, D., 1980. Authigener Rutil im Buntsandstein der Westeifel. Neues Jahrburch fürMineralogie, Monatshefte 3, 97–108.

Mange, M.A., Morton, A.C., 2007. Geochemistry of heavy minerals. In: Mange, M.A.,Wright, D.T. (Eds.), Heavy Minerals In Use: Developments in Sedimentology, vol.58, pp. 345–391.

Marchand, R., Brohan, L., Tournoux,M., 1980. TiO2 (B), a new formof titanium dioxide andthe potassium octatitanate K2Ti8O17. Materials Research Bulletin 15, 1129–1133.

Marvin, U.B., 1971. Lunar niobian rutile. Earth and Planetary Science Letters 11, 7–9.Massonne, H.-J., 2001. First find of coesite in the ultrahigh-pressure metamorphic area

of the central Erzgebirge, Germany. European Journal of Mineralogy 13, 565–570.Massonne, H.-J., Czambor, A., 2007. Geochemical signatures of Variscan eclogites from

the Saxonian Erzgebirge, central Europe. Chemie der Erde 67, 69–83.Matthews, A., Beckinsale, R.D., Durham, J.J., 1979. Oxygen isotope fractionation

between rutile and water and geothermometry of metamorphic eclogites.Mineralogical Magazine 43, 405–413.

McDonough, W.F., 1991. Partial melting of subducted oceanic-crust and isolation of itsresidual eclogitic lithology. Philosophical Transactions of the Royal Society LondonA 335, 407–418.

McDonough,W.F., Sun, S.-S., 1995. The composition of the Earth. Chemical Geology 120,223–253.

McGetchin, T.R., Silver, L.T., 1970. Compositional relations in minerals from kimberlitesand related rocks in the Moses rock dike, San Juan County, Utah. AmericanMineralogist 55, 1738–1771.

McInnes, B.I.A., Evans, N.J., Fu, F.Q., Garwin, S., 2005. Application of thermochronologyto hydrothermal ore deposits. Reviews in Mineralogy & Geochemistry 58, 467–498.

Meinhold, G., Anders, B., Kostopoulos, D., Reischmann, T., 2008. Rutile chemistry andthermometry as provenance indicator: an example from Chios Island, Greece.Sedimentary Geology 203, 98–111.

Mezger, K., Hanson, G.N., Bohlen, S.R., 1989. High-precision U–Pb ages of metamorphicrutiles: application to the cooling history of high-grade terranes. Earth and PlanetaryScience Letters 96, 106–118.

Mezger, K., Rawnsley, C.M., Bohlen, S.R., Hanson, G.N., 1991. U–Pb garnet, sphene,monazite, and rutile ages: implications for the duration of high-grademetamorphismand cooling histories, Adirondack Mts., New York. Journal of Geology 99, 415–428.

Michailidis, K.M., 1997. An EPMA and SEM study of niobian–tungstenian rutile from theFanos aplitic granite, central Macedonia, northern Greece. Neues Jahrbuch fürMineralogie, Monatshefte 12, 549–563.


Mierdel, K., Keppler, H., 2004. The temperature dependence of water solubility inenstatite. Contributions to Mineralogy and Petrology 148, 305–311.

Miller, C., Zanetti, A., Thöni, M., Konzett, J., 2007. Eclogitisation of gabbroic rocks:redistribution of trace elements and Zr in rutile thermometry in an Eo–Alpinesubduction zone (Eastern Alps). Chemical Geology 239, 96–123.

Mobbs, P.M., 1996. The mineral industry of Sierra Leone. Minerals Information. U.S.Geological Survey.

Mojzsis, S.J., Harrison, T.M., Pidgeon, R.T., 2001. Oxygen-isotope evidence from ancientzircons for liquid water at the Earth's surface 4,300 Myr ago. Nature 409, 178–181.

Möller, A., Appel, P., Mezger, K., Schenk, V., 1995. Evidence for a 2 Ga subduction zone:eclogites in the Usagaran belt of Tanzania. Geology 23, 1067–1070.

Möller, A., Mezger, K., Schenk, V., 2000. U–Pb dating of metamorphic minerals: Pan-African metamorphism and prolonged slow cooling of high pressure granulites inTanzania, East Africa. Precambrian Research 104, 123–146.

Moore, D.K., Cherniak, D.J., Watson, E.B., 1998. Oxygen diffusion in rutile from 750 to1000 °C and 0.1 to 1000 MPa. American Mineralogist 83, 700–711.

Morad, S., 1986. SEM study of authigenic rutile, anatase and brookite in Proterozoicsandstones from Sweden. Sedimentary Geology 46, 77–89.

Morton, A.C., 1985. Heavy minerals in provenance studies. In: Zuffa, G.G. (Ed.),Provenance of Arenites. Reidel, Dordrecht, The Netherlands, pp. 249–277.

Morton, A.C., 1991. Geochemical studies of detrital heavyminerals and their applicationto provenance research. In: Morton, A.C., Todd, S.P., Haughton, P.D.W. (Eds.),Developments in Sedimentary Provenance Studies: Geological Society of London,Special Publication, vol. 57, pp. 31–45.

Morton, A., Chenery, S., 2009. Detrital rutile geochemistry and thermometry as guidesto provenance of Jurassic–Paleocene sandstones of the Norwegian Sea. Journal ofSedimentary Research 79, 540–553.

Morton, A.C., Hallsworth, C.R., 1994. Identifying provenance-specific features of detritalheavy mineral assemblages in sandstones. Sedimentary Geology 90, 241–256.

Morton, A.C., Hallsworth, C.R., 1999. Processes controlling the composition of heavymineral assemblages in sandstones. Sedimentary Geology 124, 3–29.

Morton, A.C., Hallsworth, C.R., 2007. Stability of detrital heavy minerals during burialdiagenesis. In: Mange, M., Wright, D.T. (Eds.), Heavy Minerals In Use: Develop-ments in Sedimentology, vol. 58, pp. 215–245.

Morton, A., Hallsworth, C., Chalton, B., 2004. Garnet compositions in Scottish andNorwegian basement terrains: a framework for interpretation of North Seasandstone provenance. Marine and Petroleum Geology 21, 393–410.

Morton, A.C., Whitham, A.G., Fanning, C.M., 2005. Provenance of Late Cretaceous toPaleocene submarine fan sandstones in the Norwegian Sea: integration of heavymineral, mineral chemical and zircon age data. Sedimentary Geology 182, 3–28.

Mposkos, E.D., Kostopoulos, D.K., 2001. Diamonds, former coesite and supersilicicgarnet in metasedimentary rocks from the Greek Rhodope: a new ultrahigh-pressure metamorphic province established. Earth and Planetary Science Letters192, 497–506.

Mücke, A., Chaudhuri, J.N.B., 1991. The continuous alteration of ilmenite throughpseudorutile to leucoxene. Ore Geology Reviews 6, 25–44.

Mukasa, S.B., Wilson, A.H., Carlson, R.W., 1998. A multielement geochronologic study ofthe Great Dyke, Zimbabwe: significance of the robust and reset ages. Earth andPlanetary Science Letters 164, 353–369.

Müller, A., Halls, C., 2005. Rutile—the tin–tungsten host in the intrusive tourmalinebreccia at Wheal Remfry, SW England. In: Mao, J., Bierlein, F.P. (Eds.), MineralDeposit Research: Meeting the Global Challenge, pp. 441–444.

Murad, E., Cashion, J.D., Noble, C.J., Pilbrow, J.R., 1995. The chemical state of Fe in rutilefrom an albitite in Norway. Mineralogical Magazine 59, 557–560.

Mvuemba Ntanda, F., Moreau, J., Meyer, H.O.A., 1982. Particularités des inclusionscristallines primaries des diamants duKasaï, Zaïre. CanadianMineralogist 20, 217–230.

Nazarov, M.A., Demidova, S.I., Patchen, A., Taylor, L.A., 2002. Dhofar 301, 302 and 303:three new lunar highland meteorites from Oman. Lunar and Planetary ScienceXXXIII, p. 1291.

Nethaway, D.R., Prindle, A.L., Van Konynenburg, R.A., 1978. Half-life of 92Nb. PhysicalReview C 17, 1409–1413.

Neufeld, K., Ring, U., Heidelbach, F., Dietrich, S., Neuser, R.D., 2008. Omphacite texturesin eclogites of the Tauern Window: implications for the exhumation of the EclogiteZone, Eastern Alps. Journal of Structural Geology 30, 976–992.

Ohsaka, T., Izumi, F., Fujiki, Y., 1978. Raman spectrum of anatase, TiO2. Journal of RamanSpectroscopy 7, 321–324.

Okamoto, K., Maruyama, S., 2004. The eclogite–garnetite transformation in theMORB+H2O system. Physics of the Earth and Planetary Interiors 146, 283–296.

Okrusch, M., Hock, R., Schüssler, U., Brummer, A., Baier, M., Theisinger, H., 2003.Intergrown niobian rutile phases with Sc- and W-rich ferrocolumbite: an electron-microprobe and Rietveld study. American Mineralogist 88, 986–995.

Ono, S., Ito, E., Katsura, T., 2001. Mineralogy of subducted basaltic crust (MORB) from 25to 37 GPa, and chemical heterogeneity of the lower mantle. Earth and PlanetaryScience Letters 10, 57–63.

Paine, M.D., Anand, R.R., Aspandiar, M., Fitzpatrick, R.B., Verrall, M.R., 2005. Quantitativeheavy-mineral analysis of a Pliocene beach placer deposit in Southeastern Australiausing the AutoGeoSEM. Journal of Sedimentary Research 75, 742–759.

Papp, G., 2007. On the type locality of rutile (review of contemporary data about theoccurrence of the “Hungarian red schorl”). In: Jancsy, P. (Ed.), Prvenstvá nerastnejríše Slovenska — The unique minerals of Slovakia. Slovenské banské múzeum,Banská Štiavnica, pp. 51–55.

Patchett, P.J., 1983. Importance of the Lu–Hf isotopic system in studies of planetarychronology and chemical evolution. Geochimica et Cosmochimica Acta 47, 81–91.

Patchett, P.J., Kouvo, O., Hedge, C.E., Tatsumoto, M., 1981. Evolution of continental crustand mantle heterogeneity: evidence from Hf isotopes. Contributions to Mineralogyand Petrology 78, 279–297.

Patterson, C., 1956. Age of meteorites and the earth. Geochimica et Cosmochimica Acta10, 230–237.

Pearson, K., 1999. A TiO2 industry focus. Industrial Minerals, July, 56–69.Pettijohn, F.J., 1941. Persitence of heavy minerals and geologic age. Journal of Geology

49, 610–625.Phillips, W.E.A., 1973. The pre-Silurian rocks of Clare Island, Co. Mayo, Ireland, and the

age of themetamorphism of the Dalradian Ireland. Journal of the Geological Society129, 585–606.

Pirkle, F.L., Pirkle, W.A., Pirkle, E.C., 2007. Heavy-mineral sands of the Atlantic and Gulfcoastal plains. USA. In: Mange, M., Wright, D.T. (Eds.), Heavy Minerals In Use:Developments in Sedimentology, vol. 58, pp. 1145–1232.

Porto, S.P.S., Fleury, P.A., Damen, T.C., 1967. Raman spectra of TiO2, MgF2, ZnF2, FeF2, andMnF2. Physical Review 154, 522–526.

Pough, F.H., 1998. A Field Guide to Rocks and Minerals (Peterson Field Guides Series),5th edition. Houghton Mifflin, Harcourt. 416 pp.

Preston, R.J., Hartley, A., Hole, M.J., Buck, S., Bond, J., Mange-Rajetzky, M., Still, J., 1998.Integrated whole-rock trace element geochemistry and heavy-mineral chemistrystudies: aids to the correlation of continental red-bed reservoirs in the Beryl Field,U.K. North Sea. Petroleum Geoscience 4, 7–16.

Preston, J., Hartley, A., Mange-Rajetzky, M., Hole, M.J., May, G., Buck, S., 2002. Theprovenance of Triassic continental sandstones from the Beryl Field, northern NorthSea: mineralogical, geochemical, and sedimentological constraints. Journal ofSedimentary Research 72, 18–29.

Prinz, M., Manson, D.V., Hlava, P.F., Keil, K., 1975. Inclusions in diamonds: garnetlherzolite and eclogite assemblages. Physics and Chemistry of the Earth 9, 797–815.

Putnis, A., 1978. The mechanism of exsolution of hematite from natural iron-bearingrutile. Physics and Chemistry of Minerals 3, 183–197.

Putnis, A., Wilson, M.M., 1978. A study of iron-bearing rutiles in the paragenesis TiO2–Al2O3–P2O5–SiO2. Mineralogical Magazine 42, 255–263.

Raman, K.V., Jackson, M.L., 1965. Rutile and anatase determination in soils andsediments. American Mineralogist 50, 1086–1092.

Ramdohr, P., 1963. Beobachtungen am Opakerzbestand einiger Meteoriten besondersvon New South Wales. Chemie der Erde 23, 119–145.

Ramdohr, P., 1965. Über Mineralbestand von Pallasiten und Mesosideriten und einigegenetische Überlegungen. Monatsberichte der Deutschen Akademie der Wis-senschaftten zu Berlin 7, 923–938.

Rauch, M., Keppler, H., 2004. Water solubility in orthopyroxene. Contributions toMineralogy and Petrology 143, 525–536.

Reiners, P.W., Brandon, M.T., 2006. Using thermochronology to understand orogenicerosion. Annual Review of Earth and Planetary Sciences 34, 419–466.

Reiners, P.W., Spell, T.L., Nicolescu, S., Zanetti, K.A., 2004. Zircon (U–Th)/Hethermochonometry: He diffusion and comparisons with 40Ar/39Ar dating. Geochi-mica et Cosmochimica Acta 68, 1857–1887.

Reyneke, L., Wallmach, T., 2007. Characterization of FeTi-oxide species occuring in theRanobe heavy mineral deposit, Madagascar. The 6th International Heavy MineralsConference ‘Back to Basics’, The Southern African Institute of Mining and Metallurgy,pp. 151–158.

Rice, C., Darke, K., Still, J., 1998. Tungsten-bearing rutile from the Kori Kollo gold mineBolívia. Mineralogical Magazine 62, 421–429.

Richards, J.P., Krogh, T.E., Spooner, E.T.C., 1988. Fluid inclusion characteristics and U–Pbrutile age of late hydrothermal alteration and veining at the Musoshi stratiformcopper deposit, Central African copper belt, Zaire. Economic Geology 83, 118–139.

Ripp, G.S., Karmanov, N.S., Doroshkevich, A.G., Badmatsyrenov, M.V., Izbrodin, I.A.,2006. Chrome-bearing mineral phases in the carbonatites of northern Transbaika-lia. Geochemistry International 44, 395–402.

Romé de l'Isle, J.B.L. de, 1783. Cristallographie, ou description des formes propres à tousles corps du règne minéral, dans l'état de combinaison saline, pierreuse, oumétallique. Paris.

Romer, R.L., Rötzler, J., 2001. P–T–t evolution of ultrahigh-temperature granulites fromthe Saxon Granulite Massif, Germany. Part II: geochronology. Journal of Petrology42, 2015–2032.

Rossman, G.R., Smyth, J.R., 1990. Hydroxyl contents of accessory minerals in mantleeclogites and related rocks. American Mineralogist 76, 765–780.

Roth, R.S., Coughanour, L.W., 1955. Phase equilibrium relationships in the systemtitania–niobia and zirconia–niobia. Journal of Research of the National Bureau ofStandards 55, 209–213.

Roy, P.S., 1999. Heavy mineral beach placers in southeastern Australia: their nature andgenesis. Economic Geology 94, 567–588.

Rubatto, D., Hermann, J., 2001. Exhumation as fast as subduction. Geology 29, 3–6.Rudnick, R.L., Fountain, D.M., 1995. Nature and composition of the continental crust: a

lower crustal perspective. Reviews of Geophysics 33, 267–309.Rudnick, R.L., Barth, M., Horn, I., McDonough, W.F., 2000. Rutile-bearing refractory

eclogites:missing linkbetween continents anddepletedmantle. Science287, 278–281.Sakoma, E.M., Martin, R.F., 2002. Oxidation-induced postmagmatic modifications of

primary ilmenite, NYG-related aplite dyke, Tibchi Complex, Kalato, Nigeria.Mineralogical Magazine 66, 591–604.

Salters, V.J.M., Zindler, A., 1995. Extreme 176Hf/177Hf in the sub-oceanic mantle. Earthand Planetary Science Letters 129, 13–30.

Sasaki, J., Peterson, N.L., Hoshino, K., 1985. Tracer impurity diffusion in single-crystalrutile (TiO2−x). Journal of Physics and Chemistry of Solids 46, 1267–1283.

Schandl, E.S., Davis, D.W., Krogh, T.E., 1990. Are the alteration halos of massive sulfidedeposits syngenetic? Evidence from U–Pb dating of hydrothermal rutile at the Kiddvolcanic center, Abitibi subprovince, Canada. Geology 18, 505–508.

Schärer, U., Labrousse, L., 2003. Dating the exhumation of UHP rocks and associatedcrustal melting in the Norwegian Caledonides. Contribution to Mineralogy andPetrology 144, 758–770.


Schärer, U., Krogh, T.E., Gower, C.F., 1986. Age and evolution of the Grenville Province ineastern Labrador from U–Pb systematics of accessory minerals. Contribution toMineralogy and Petrology 94, 438–451.

Scherer, E., Münker, C., Mezger, K., 2001. Calibration of the lutetium–hafnium clock.Science 293, 683–687.

Schlüter, T., 2008. Geological Atlas of Africa, With Notes on Stratigraphy, Tectonics,Economic Geology, Geohazards, Geosites and Geoscientific Education of EachCountry, 2nd edition. Springer-Verlag, Berlin. 307 pp.

Schmidt, A., Weyer, S., John, T., Brey, G.P., 2009. HFSE systematics of rutile-bearingeclogites: new insights into subduction zone processes and implications for theEarth's HFSE budget. Geochimica et Cosmochimica Acta 73, 455–468.

Schmitz, M.D., Bowring, S.A., 2003. Constraints on the thermal evolution ofcontinental lithosphere from U–Pb accessory mineral thermochronometry oflower crustal xenoliths, southern Africa. Contribution to Mineralogy andPetrology 144, 592–618.

Schönbächler, M., Rehkämper, M., Halliday, A.N., Lee, D.-C., Bourot-Denise, M., Zanda, B.,Hattendorf, B., Günther, D., 2002. Niobium–zirconium chronometry and early solarsystem development. Science 295, 1705–1708.

Schönbächler, M., Lee, D.-C., Rehkämper, M., Halliday, A.N., Hattendorf, B., Günther, D.,2005. Nb/Zr fractionation on the Moon and the search for extinct 92Nb. Geochimicaet Cosmochimica Acta 69, 775–785.

Schulze, D.J., 1990. Silicate-bearing rutile-dominated nodules from South Africankimberlites: metasomatized cumulates. American Mineralogist 75, 97–104.

Scott, K.M., 1988. Phyllosilicate and rutile compositions as indicators of Sn specializationin some southeastern Australian granites. Mineralium Deposita 23, 159–165.

Scott, K.M., 2005. Rutile geochemistry as a guide to porphyry Cu–Au mineralization,Northparkes, New South Wales, Australia. Geochemistry: Exploration, Environ-ment, Analysis 5, 247–253.

Scott, K.M., Radford, N.W., 2007. Rutile compositions at the Big Bell Au deposit as aguide for exploration. Geochemistry: Exploration, Environment, Analysis 7,353–361.

Sguigna, A.P., Larabee, A.J., Waddington, J.C., 1982. The half-life of 176Lu by a γ–γcoincidence measurement. Canadian Journal of Physics 60, 361–364.

Shannon, R.D., 1976. Revised effective ionic radii and systematic studies of interatomicdistances in halides and chalcogenides. Acta Crystallographica A32, 751–767.

Sharp, T.G., El Goresy, A., Wopenka, B., Chen, M., 1999. A post-stishovite SiO2 polymorphin the meteorite Shergotty: implications for impact events. Science 284,1511–1513.

Shau, Y.-H., Yang, H.-Y., Peacor, D.R., 1991. On oriented titanite and rutile inclusions insagenitic biotite. American Mineralogist 76, 1205–1217.

Simons, P.Y., Dachille, F., 1967. The structure of TiO2-II, a high pressure phase of TiO2.Acta Crystallographica 23, 334–335.

Sircombe, K., 1995. SHRIMP ion probe provenance studies of heavy detrital minerals incoastal sands and sedimentary rocks of east Australia. Abstracts, Third AustralianConference on Geochronology and Isotope Geoscience, Perth,WA, Curtin Universityof Technology, p. 32.

Sircombe, K.N., 1997. Detrital mineral SHRIMP geochronology and provenance analysisof sediments in Eastern Australia. Unpubl. PhD dissertation, Australian NationalUniversity, Canberra.

Smith, D., Perseil, E.-A., 1997. Sb-rich rutile in the manganese concentrations at St.Marcel-Praborna, Aosta Valley, Italy; petrology and crystal-chemistry. Mineralog-ical Magazine 61, 655–669.

Smith, S.J., Stevens, R., Liu, S., Li, G., Navrotsky, A., Boerio-Goates, J., Woodfield, B.F.,2009. Heat capacities and thermodynamic functions of TiO2 anatase and rutile:analysis of phase stability. American Mineralogist 94, 236–243.

Smythe, D.J., Schulze, D.J., Brenan, J.M., 2008. Rutile as a kimberlite indicator mineral:minor and trace element geochemistry. 9th International Kimberlite Conference,Extended Abstract, No. 9IKC-A-00193.

Sobolev, N.V., Yefimova, E.S., 2000. Composition and petrogenesis of Ti-oxidesassociated with diamonds. International Geology Review 42, 758–767.

Sobolev, N.V., Kaminsky, F.V., Griffin, W.L., Yefimova, E.S., Win, T.T., Ryan, C.G.,Botkunov, A.I., 1997. Mineral inclusions in diamonds from the Sputnik kimberlitepipe, Yakutia. Lithos 39, 135–157.

Spear, F.S., Wark, D.A., Cheney, J.T., Schumacher, J.C., Watson, B., 2006. Zr-in-rutilethermometry in blueschists from Sifnos, Greece. Contributions to Mineralogy andPetrology 152, 375–385.

Spurr, R., Myers, H., 1957. Quantitative analysis of anatase-rutile mixtures with an X-ray diffractometer. Analytical Chemistry 29, 760–762.

Stacey, J.S., Kramers, J.D., 1975. Approximation of terrestrial lead-isotope evolution by atwo stage model. Earth and Planetary Science Letters 26, 359–362.

Stanaway, K.J., 1994. Overview of titanium dioxide feedstocks. Mining Engineering,December, 1367–1370.

Stendal, H., Toteu, S.F., Frei, R., Penaye, J., Njel, U.O., Bassahak, J., Nni, J., Kankeu, B.,Ngako, V., Hell, J.V., 2006. Derivation of detrital rutile in the Yaoundé region fromthe Neoproterozoic Pan-African belt in southern Cameroon (Central Africa). Journalof African Earth Sciences 44, 443–458.

Stockli, D.F., Farley, K.A., Walker, J.D., Blackburn, T.J., 2005. Helium diffusion and (U–Th)/He thermochronometry of monazite and rutile. Geochimica et CosmochimicaActa 69 (10, Supplement 1) A8.

Stockli, D.F., Wolfe, M.R., Blackburn, T.J., Zack, T., Walker, J.D., Luvizotto, G.L., 2007. Hediffusion and (U–Th)/He thermochronometry of rutile. Eos, Transactions of theAmerican Geophysical Union, Fall Meeting Supplement, Abstract V23C-1548.

Taylor, W.R., 2008. Rutile U–Pb dating in diamond exploration — application to detritalheavy mineral provenance studies and kimberlite age dating. 9th InternationalKimberlite Conference, Extended Abstract, No. 9IKC-A-00373.

Temple, A.K., 1966. Alteration of ilmenite. Economic Geology 61, 695–714.

Tera, F., Wasserburg, G.J., 1972. U–Th–Pb systematics in three Apollo 14 basalts and theproblemof initial Pb in lunar rocks. Earth and Planetary Science Letters 17, 281–304.

Teufer, G., Temple, A.K., 1966. Pseudorutile―a new mineral intermediate betweenilmenite and rutile in the natural alteration of ilmenite. Nature 211, 179–181.

Tien, T.Y., Rosen, J.J., Bigelow, W.C., Sanvordenker, V., 1969. Microhardness of TiO2–

Nb2O3 solid solutions. Journal of the American Ceramic Society 52, 520.Tiepolo, M., Vannucci, R., Oberti, R., Foley, S., Bottazzi, P., Zanetti, A., 2000. Nb and Ta

incorporation and fractionation in titanian pargasite and kaersutite: crystal–chemical constraints and implications for natural systems. Earth and PlanetaryScience Letters 176, 185–201.

Tollo, R.P., Haggerty, S.E., 1987. Nb–Cr-rutile in the Orapa kimberlite, Botswana.Canadian Mineralogist 25, 251–264.

Tomkins, H.S., Powell, R., Ellis, D.J., 2007. The pressure dependence of the zirconium-in-rutile thermometer. Journal of Metamorphic Geology 25, 703–713.

Tompsett, G.A., Bowmaker, G.A., Cooney, R.P., Metson, J.B., Rodgers, K.A., Seakins, J.M.,1995. The Raman spectrum of brookite, TiO2 (Pbca, Z=8). Journal of RamanSpectroscopy 26, 57–62.

Trengove, L., 1972. William Gregor (1761–1817) discoverer of titanium. Annals ofScience 29, 361–395.

Triebold, S., von Eynatten, H., Luvizotto, G.L., Zack, T., 2007. Deducing source rock lithologyfrom detrital rutile geochemistry: an example from the Erzgebirge, Germany.Chemical Geology 244, 421–436.

Uher, P., Černý, P., Chapman, R., Határ, J., Miko, O., 1998. Evolution of Nb, Ta-oxideminerals in the Prašivá granitic pegmatites, Slovakia. I. Primary Fe, Ti-richassemblage. Canadian Mineralogist 36, 525–534.

Uher, P., Žitňan, P., Ozdín, D., 2007. Pegmatitic Nb–Ta oxide minerals in alluvial placersfrom Limbach, Bratislava Massif, Western Carpathians, Slovakia: compositionalvariations and evolutionary trend. Journal of Geosciences 52, 133–141.

Urban, A.J., Hoskins, B.F., Grey, I.E., 1992. Characterization of V–Sb–W-bearing rutilefrom the Hemlo gold deposit, Ontario. Canadian Mineralogist 30, 319–326.

Vaggelli, G., Borghi, A., Calusi, S., Cossio, R., Giuntini, L., Massi, M., 2007. Micro-PIXEdetermination of Zr in rutile: an application to geothermometry of high-P rocksfrom the Western Alps (Italy). Proceedings of the XI International Conference onPIXE and its Analytical Applications Puebla, Mexico, May 25–29.

Valentine, P.C., Commeau, J.A., 1990. Fine-grained rutile in the Gulf of Maine—diageneticorigin, source rocks, and sedimentary environment of deposition. Economic Geology85, 862–876.

Valley, J.W., 2003. Oxygen isotopes in zircon. In: Hanchar, J.M., Hoskin, P.W.O. (Eds.),Zircon: Reviews in Mineralogy and Geochemistry, vol. 53, pp. 343–380.

Valley, J.W., Lackey, J.S., Cavosie, A.J., Clechenko, C.C., Spicuzza, M.J., Basei, M.A.S.,Bindeman, I.N., Ferreira, V.P., Sial, A.N., King, E.M., Peck, W.H., Sinha, A.K., Wei, C.S.,2005. 4.4 billion years of crustal maturation: oxygen isotope ratios of magmaticzircon. Contributions to Mineralogy and Petrology 150, 561–580.

VanRoermund,H.L.M.,Drury,M.R., Barnhoorn,A.,DeRonde,A., 2000.Non-silicate inclusionsin garnet from an ultra-deep orogenic peridotite. Geological Journal 35, 209–229.

Villaseca, C., Orejana, D., Paterson, B.A., 2007. Zr–LREE rich minerals in residualperaluminous granulites, another factor in the origin of low Zr–LREE graniticmelts? Lithos 96, 375–386.

Vlassopoulos, D., Rossman, G.R., Haggerty, S.E., 1993. Coupled substitution of H andminor elements in rutile and their implications of OH contents in Nb- and Cr-richrutile from the upper mantle. American Mineralogist 78, 1181–1191.

Vogel, D.E., Garlick, G.D., 1970. Oxygen isotope ratios in metamorphic eclogites.Contributions to Mineralogy and Petrology 28, 183–191.

Von Born, I., 1772. Lithophylacium Bornianum, Index Fossilium, quae collegit, et inClasses ac Ordines disposuit Ignatius Eques a Born. Vol. 1, Gerle, Prague, 157 pp.

Von Eynatten, H., Gaupp, R., 1999. Provenance of Cretaceous synorogenic sandstonesfrom the Eastern Alps: constraints from framework petrography, heavy mineralanalysis, and mineral chemistry. Sedimentary Geology 124, 81–111.

Von Eynatten, H., Tolosana-Delgado, R., Triebold, S., Zack, T., 2005. Interactions betweengrain size and composition of sediments: two examples. Proceedings of the 2ndCompositional Data Analysis Workshop, 19–21 October 2005, Girona, Spain.

Von Quadt, A., Moritz, R., Peytcheva, I., Heinrich, C.A., 2005. Geochronology andgeodynamics of Late Cretaceous magmatism and Cu–Au mineralization in thePanagyurishte region of the Apuseni–Banat–Timok–Srednogorie belt, Bulgaria. OreGeology Reviews 27, 95–126.

Vry, J.K., Baker, J.A., 2006. LA-MC-ICPMS Pb–Pb dating of rutile from slowly cooledgranulites: confirmation of the high closure temperature for Pb diffusion in rutile.Geochimica et Cosmochimica Acta 70, 1807–1820.

Wade, J., Wood, B.J., 2001. The Earth's ‘missing’ niobiummay be in the core. Nature 409,75–78.

Wadhwa, M., Amelin, Y., Davis, A.M., Lugmair, G.W., Meyer, B., Gounelle, M., Desch, S.J.,2007. From dust to planetesimals: implications for the solar protoplanetary diskfrom short-lived radionuclides in meteorites. In: Reipurth, B., Jewitt, D., Keil, K.(Eds.), Protostars and Planets V. University of Arizona Press, Tucson, pp. 835–848.

Watson, T.L., 1922. Rutile–ilmenite intergrowth. American Mineralogist 7, 185–188.Watson, E.B., Wark, D.A., Thomas, J.B., 2006. Crystallization thermometers for zircon

and rutile. Contributions to Mineralogy and Petrology 151, 413–433.Wetherill, G.W., 1956. Discordant uranium–lead ages, I. Transactions of the American

Geophysical Union 37, 320–326.Whitham, A.G., Morton, A.C., Fanning, C.M., 2004. Insights into Cretaceous–Palaeogene

sediment transport paths and basin evolution in the North Atlantic from a heavymineral study of sandstones from southern East Greenland. Petroleum Geoscience10, 61–72.

Wilde, S.A., Valley, J.W., Peck, W.H., Graham, C.M., 2001. Evidence from detrital zirconsfor the existence of continental crust and oceans on the Earth 4.4 Gyr ago. Nature409, 175–178.


Williams, I.S., 1998. U–Th–Pb geochronology by ion microprobe. In: McKibben, M.A.,Shanks III, W.C., Ridley, W.I. (Eds.), Applications of Microanalytical Techniques toUnderstandingMineralising Processes: Reviews in EconomicGeology, vol. 7, pp. 1–35.

Williams, S.A., Cesbron, F.P., 1977. Rutile and apatite: useful prospecting guides forporphyry copper deposits. Mineralogical Magazine 41, 288–292.

Wise, M.A., 1981. Blue quartz in Virginia. Virginia Minerals 27, 9–13.Withers, A.C., Essene, E.J., Zhang, Y., 2003. Rutile/TiO2II phase equilibria. Contributions

to Mineralogy and Petrology 145, 199–204.Wolfe,M.R., Stockli, D.F., Shuster,D.L.,Walker, J.D.,MacPherson,G.L., 2007.Assessmentof the

rutile (U–Th)/He thermochronometry on the KTB drill hole, Germany. Eos, Transactionsof the American Geophysical Union, Fall Meeting Supplement, Abstract V23C-1549.

Wong, L., Davis, D.W., Krogh, T.E., Robert, F., 1991. U–Pb zircon and rutilegeochronology of Archean greenstone formation and gold mineralization in theVal d'Or region, Quebec. Earth and Planetary Science Letters 104, 325–336.

Wood, J.A., Marvin, U.B., Powell, B.N., Dickey Jr., J.S., 1970. Mineralogy and petrology ofthe Apollo 11 Lunar sample. Smithsonian Astrophysical Observatory Special Report307, 1–99.

Wu, X., Meng, D., Han, Y., 2005. α-PbO2-type nanophase of TiO2 from coesite-bearingeclogite in the Dabie Mountains, China. American Mineralogist 90, 1458–1461.

Xiao, Y., Sun, W., Hoefs, J., Simon, K., Zhang, Z., Li, S., Hofmann, A.W., 2006. Makingcontinental crust through slab melting: Constraints from niobium–tantalumfractionation in UHP metamorphic rutile. Geochimica et Cosmochimica Acta 70,4770–4782.

Ye, K., Cong, B., Ye, D., 2000. The possible subduction of continental material to depthsgreater than 200 km. Nature 407, 734–736.

York, D., 1967. The best isochrone. Earth and Planetary Science Letters 2, 479–482.York, D., 1969. Least squares fitting of a straight line with correlated errors. Earth and

Planetary Science Letters 5, 320–324.Zack, T., Luvizotto, G.L., 2006. Application of rutile thermometry to eclogites.

Mineralogy and Petrology 88, 69–85.Zack, T., Kronz, A., Foley, S.F., Rivers, T., 2002. Trace element abundances in rutiles from

eclogites and associated garnet mica schists. Chemical Geology 184, 97–122.

Zack, T., Moraes, R., Kronz, A., 2004a. Temperature dependence of Zr in rutile: empiricalcalibration of a rutile thermometer. Contributions toMineralogy and Petrology 148,471–488.

Zack, T., von Eynatten, H., Kronz, A., 2004b. Rutile geochemistry and its potential use inquantitative provenance studies. Sedimentary Geology 171, 37–58.

Zack, T., Luvizotto, G.L., Stockli, D.F., Barth, M., 2008. Texturally controlled U/Pb dating ofrutile from the Ivrea Zone. Geochimica et Cosmochimica Acta 72 (12, Supplement 1)A1069.

Zhang, J., Jin, Z., Green, H.W., Jin, S., 2001. Hydroxyl in continental deep subductionzone: evidence from UHP eclogites of the Dabie Mountains. Chinese ScienceBulletin 46, 592–596.

Zhang, R.Y., Zhai, S.M., Fei, Y.W., Liou, J.G., 2003. Titanium solubility in coexisting garnetand clinopyroxene at very high pressure: the significance of exsolved rutile ingarnet. Earth and Planetary Science Letters 216, 591–601.

Zhang, Z.M., Liou, J.G., Zhao, X.D., Shi, C., 2006. Petrogenesis of Maobei rutile eclogitesfrom the southern Sulu ultrahigh-pressure metamorphic belt, eastern China.Journal of Metamorphic Geology 24, 727–741.

Zhao, D., Essene, E.J., Zhang, Y., 1999. An oxygen barometer for rutile–ilmeniteassemblages: oxidation state ofmetasomatic agents in themantle. Earth and PlanetaryScience Letters 166, 127–137.

Zheng, Y.F., 1991. Calculation of oxygen isotope fractionation in metal oxides.Geochimica et Cosmochimica Acta 55, 2299–2307.

Zheng, Y.F., Fu, B., Xiao, Y., Li, Y., Gong, B., 1999. Hydrogen and oxygen isotope evidencefor fluid–rock interactions in the stages of pre- and post-UHPmetamorphism in theDabie Mountains. Lithos 46, 677–693.

Zheng, Y.F., Fu, B., Gong, B., Li, L., 2003. Stable isotope geochemistry of ultrahighpressure metamorphic rocks from the Dabie–Sulu orogen in China: implications forgeodynamics and fluid regime. Earth-Science Reviews 62, 105–161.

Zolensky, M.E., Sylvester, P.J., Paces, J.B., 1988. Origin and significance of blue colorationin quartz from Llano rhyolite (Ilanite), north-central Llano County, Texas. AmericanMineralogist 73, 313–323.

Rutile and its applications in earth sciences · · 2010-08-13Rutile and its applications in...

Documents

Transcript of Rutile and its applications in earth sciences · · 2010-08-13Rutile and its applications in...