PLEASE SCROLL DOWN FOR ARTICLE - Miami University · and dynamic recrystallization were most common...

PLEASE SCROLL DOWN FOR ARTICLE

This article was downloaded by: [TÜBTAK EKUAL]On: 1 September 2009Access details: Access Details: [subscription number 772815469]Publisher Taylor & FrancisInforma Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House,37-41 Mortimer Street, London W1T 3JH, UK

International Geology ReviewPublication details, including instructions for authors and subscription information:http://www.informaworld.com/smpp/title~content=t902953900

Geology and geochemistry of the synextensional Salihli granitoid in theMenderes core complex, western Anatolia, TurkeyZeynep Oner a; Yildirim Dilek a; Yusuf K. Kadioglu b

a Department of Geology, Miami University, Oxford, OH 45056, USA b Department of Geological Engineering,University of Ankara, Tandogan, Ankara, Turkey

First Published on: 03 June 2009

To cite this Article Oner, Zeynep, Dilek, Yildirim and Kadioglu, Yusuf K.(2009)'Geology and geochemistry of the synextensional Salihligranitoid in the Menderes core complex, western Anatolia, Turkey',International Geology Review,99999:1,

To link to this Article: DOI: 10.1080/00206810902815871

URL: http://dx.doi.org/10.1080/00206810902815871

Full terms and conditions of use: http://www.informaworld.com/terms-and-conditions-of-access.pdf

This article may be used for research, teaching and private study purposes. Any substantial orsystematic reproduction, re-distribution, re-selling, loan or sub-licensing, systematic supply ordistribution in any form to anyone is expressly forbidden.

The publisher does not give any warranty express or implied or make any representation that the contentswill be complete or accurate or up to date. The accuracy of any instructions, formulae and drug dosesshould be independently verified with primary sources. The publisher shall not be liable for any loss,actions, claims, proceedings, demand or costs or damages whatsoever or howsoever caused arising directlyor indirectly in connection with or arising out of the use of this material.

http://www.informaworld.com/smpp/title~content=t902953900

http://dx.doi.org/10.1080/00206810902815871

http://www.informaworld.com/terms-and-conditions-of-access.pdf

Geology and geochemistry of the synextensional Salihli granitoid in theMenderes core complex, western Anatolia, Turkey

Zeynep Onera*, Yildirim Dileka and Yusuf K. Kadioglub

aDepartment of Geology, Miami University, Shideler Hall, Oxford, OH 45056, USA;bDepartment of Geological Engineering, University of Ankara, Tandogan, Ankara, Turkey

(Accepted 11 February 2009 )

The Miocene Salihli granitoid (SG) in the footwall of the Alasehir detachment in

the Menderes core complex is a synextensional intrusion, providing important

structural, geochronological, and geochemical constraints on the nature of late

Cenozoic magmatism associated with crustal extension in the Aegean province.

The NW–SE elongated pluton crosscuts the extensional mylonitic fabric in the

metamorphic host rocks but is foliated, mylonitized, and cataclastically deformed

in a ,100-m-thick shear zone along the detachment. Mylonitic granitoids range

from ultramylonites to protomylonites, and exhibit ductile deformation

structures showing consistently top-to-the north shearing. Grain-size reduction

and dynamic recrystallization were most common deformational mechanisms

producing the structural fabric of the mylonitic granitoid rocks. This earlier

ductile fabric is overprinted by north-dipping cataclastic foliation that developed

sub-parallel to the Alasehir detachment and its shear zone. Crystallization and

cooling ages of the SG are nearly coeval with the documented early Miocene ages

of metamorphism and deformation in its host rocks. The SG pluton ranges in

composition from granite, granodiorite, and alkali-feldspar granite, to monzo-

granite, and syenogranite; it consists of metaluminous to slightly peraluminous,

high-K calc-alkaline rocks with silica contents between 62.36 and 73.95 wt-%.

The rocks are enriched in LILE and depleted in HFSE, and show strong negative

anomalies in Ba, Nb, Sr, P, and Ti. These geochemical features suggest derivation

of the SG melts from a subduction-metasomatized, subcontinental lithospheric

mantle. Invasion of the lower and middle crust by mantle-derived melts triggered

MASH-type processes (melting, assimilation, storage, homogenization), resulting

in the production of hybrid SG magmas. Asthenospheric upwelling caused by

lithospheric delamination was a likely heat source that triggered the inferred

partial melting of the mantle lithosphere. Continued extensional deformation and

unroofing of the Menderes core complex and the synextensional SG in the mid to

late Miocene was accompanied by the formation of an asymmetric supradetach-

ment basin in the hanging wall of the Alasehir detachment.

Keywords: Menderes metamorphic core complex; synextensional magmatism;

metaluminous granitoids; detachment surface; mylonitic deformation; cataclastic

deformation; crustal exhumation; partial melting of mantle lithosphere; hybrid

magmatism; Aegean Province; western Anatolia, Turkey

*Corresponding author. Email: [email protected]

International Geology Review

2009, iFirst Article, 1–33

ISSN 0020-6814 print/ISSN 1938-2839 online# 2009 Taylor & FrancisDOI: 10.1080/00206810902815871http://www.informaworld.com

Downloaded By: [TÜBTAK EKUAL] At: 06:48 1 September 2009

Introduction

Synextensional magmatism during the Oligo-Miocene and Miocene produced

widespread plutons in the broader Aegean region (Altherr et al. 1988; Altherr and

Siebel 2002; Pe-Piper and Piper 2002, 2006; Pe-Piper et al. 2002; Akay and Erdogan

2004; Bozkurt 2004; Gessner et al. 2004; Isik et al. 2004; Koprubasi and Aldanmaz

2004; Innocenti et al. 2005; Ring and Collins 2005; Agostini et al. 2007; Dilek and

Altunkaynak 2007; Akay 2008). These plutons are mainly represented by I-type

granitoids, whose compositions and geochemical fingerprints show significant

variations (Altherr and Siebel 2002). Therefore, the melt sources, the magmatic

evolution, and the nature of the heat source for the production of these

synextensional granitoids in the Aegean province are critical to better constrain

the late Cenozoic geodynamic evolution of this region. Furthermore, deformed

granitoid plutons occurring in the footwalls of major detachment surfaces of

metamorphic core complexes in the region provide critical information on the

spatial and temporal relations, and the interplay between tectonics and magmatism

in continental extension. Igneous and tectonic structures in these granitoid rocks can

be used effectively to constrain the time-progressive evolution of extensional

deformation and synextensional magmatism in four dimensions.

In this paper we present new structural and geochemical data from the Miocene

SG in the Menderes metamorphic core complex of western Anatolia (Figure 1),

documenting its synextensional deformation patterns, geochemical character, and

tectonomagmatic evolution. We discuss its melt source and petrogenesis in a

regional tectonic framework. The SG presents a case study of continental

extensional magmatism in a subduction zone environment.

Geology of the Menderes metamorphic massif

The Menderes metamorphic massif farther south in the Anatolide block is a NE–

SW-oriented, sub-elliptical dome divided into northern, central, and southern

sections that are separated by nearly E–W-trending structural grabens (Figure 2). It

consists of a Precambrian ‘core’ and Palaeozoic-Cenozoic ‘cover’ (Satir and

Friedrichsen 1986; Bozkurt and Park 1994; Bozkurt and Oberhansli 2001, and

references therein). The core sequence includes augen gneisses, metagranites, high-

grade schists, and eclogitic metagabbros with metamorphic ages older than 50 Ma

(Candan et al. 2001; Bozkurt and Oberhansli 2001). The cover sequence consists of

various schist types and metamorphosed carbonates, and the protoliths of the cover

sequences range in age from Palaeozoic to the early Eocene (Loos and Rischmann

1999; Bozkurt and Oberhansli 2001; Rimmele et al. 2003). The core and cover

sequences of the Menderes massif collectively comprise several nappe systems that

were assembled mainly during the late Mesozoic–early Cenozoic collisional events in

the region (Gessner et al. 2001b; Ring et al. 2001; Reignier et al. 2007).

The main episode of metamorphism in the Menderes massif is inferred to have

resulted from the burial regime associated with the emplacement of the Lycian

nappes and ophiolitic thrust sheets (Dilek and Whitney 2000; Yilmaz 2002).

Imbricate stacking of the Menderes nappes beneath the Lycian nappes and

ophiolitic thrust sheets appears to have migrated southwards throughout the

Palaeocene–middle Eocene (Ozer et al. 2001; Candan et al. 2005). The unroofing

and exhumation of the Menderes massif may have started as early as in the latest

Oligocene-early Miocene (25–21 Ma) as constrained by the cooling ages of the

2 Z. Oner et al.


synextensional granitoid intrusions crosscutting the metamorphic rocks (Isik et al.

2003; Ring and Collins 2005; Thomson and Ring 2006; Bozkurt and Satir 2000;

Catlos et al. 2002). The Simav detachment along the northern edge of the northern

submassif (Isik et al. 2003; Ring and Collins 2005) and the Alasehir and Buyuk

Menderes (or Guney) detachments along the northern and southern edges

(respectively) of the central submassif (Figure 2; Gessner et al. 2001b) played a

major role in the exhumation of the Menderes massif as a core complex.

Geology and structure of the SG

Field occurrence and mineralogy of the SG pluton

The SG is one of three major granitoid bodies (including the Turgutlu and Alasehir

plutons) that occur along a ,E–W-trending belt in the footwall of the Alasehir

detachment in the central submassif of the Menderes core complex (Figure 2). All

three plutons are intrusive into the metasedimentary rocks and schists of the

Menderes massif. The compositions of the analysed SG rocks range from granite,

granodiorite, alkali feldspar granite to syenogranite and monzogranite according to

QAPF of Streckeisen (1979). The texture of the relatively undeformed SG is

generally observed as holocrystalline, fine-to-coarse grained or locally porphyritic.

Figure 1. Tectonic map of the Aegean and eastern Mediterranean region, showing the mainplate boundaries, major suture zones, and fault systems. Thick, white arrows depict thedirection and magnitude (mm/yr) of plate convergence; grey arrows mark the direction ofextension (Miocene-Recent).Note: BF – Burdur fault; DKF – Datca-Kale fault (part of the SW Anatolian Shear Zone);EAFZ – East Anatolian fault zone; EF – Ecemis fault; EKP – Erzurum-Kars Plateau; IASZ –Izmir-Ankara suture zone; IPS – Intra-Pontide suture zone; ITS – Inner-Tauride suture; KF –Kefalonia fault; KOTJ – Karliova triple junction; MM – Menderes massif; MS – MarmaraSea; MTR – Maras triple junction; NAFZ – North Anatolian fault zone; OF – Ovacik fault;PSF – Pampak-Sevan fault; TF – Tutak fault; TIP – Turkish-Iranian plateau (modified fromDilek 2006).

International Geology Review 3


Figure 2. Geological map of southwestern Anatolia, showing the distribution of theMenderes metamorphic core complex, Neotethyan ophiolites, Cenozoic sedimentary basinsand volcanic units, and salient fault systems. Major tectonic blocks and suture zones are alsodepicted.Note: AF – Acigol fault; BFZ – Burdur fault zone; DF – Datca fault; IASZ – Izmir-Ankarasuture zone; KF – Kale fault; SWASZ – Southwest Anatolian shear zone. Key to lettering forthe detachment faults: AD – Alasehir detachment; GD – Guney detachment; SD – Simavdetachment. Key to lettering for the granitoid plutons: AG – Alasehir, BG – Baklan, EP –Eybek, KG – Kozak, KOP – Koyunoba, SG – Salihli, TG –Turgutlu.

4 Z. Oner et al.


Plutonic rocks are mainly composed of quartz, orthoclase, microcline, oligoclase,

and biotite with rare muscovite. Titanite, orthite, epidote (allanite), zircon,

monazite, apatite, and opaque minerals also occur as accessory minerals. Quartz

grains are generally anhedral in shape, and plagioclase commonly occurs as

subhedral grains. Albite and Carlsbad twinning in feldpars are common features

observed in thin-section.

Sericitization and argillitization are the main alteration forms affecting the

plagioclase. Epidotization is also observed locally along the rims and fractures of the

plagioclase grains. Orthoclase is mainly observed as perthite as a result of the same

alteration mechanisms. Biotite is commonly subhedral to rarely anhedral, and is

light to dark brown in colour. Quartz, biotite and accessory minerals occur as

inclusions in the alkali feldspar grains. Some of the biotite grains include apatite and

zircon as inclusions. Clusters of biotite grains in some rocks may suggest magmatic

segregation of biotite during early crystallization of the pluton.

The SG is cut by 1- to 50-cm-thick individual dike that are composed of alkali

feldspar granite and granite porphyry. Alkali feldspar granite dikes are pink in

colour and have a fine-grained phaneritic texture in outcrop. Hydrothermal epidote

occurs along cracks in feldspar in these dikes. The dikes contain less the 5 modal %

of mafic minerals. Some of the biotite is replaced by chlorite.

Alasehir shear zone and the associated ductile to cataclastic deformation

The gently north-dipping (15–30u) Alasehir detachment surface separates the high-

grade metamorphic rocks of the Menderes core complex and the SG in the

footwall from the Neogene basin fill in the hanging wall (Figures 3 and 4). The

Salihli pluton crosscutting the Menderes core complex is exposed within and below

the Alasehir shear zone associated with this detachment fault and crops out over

an area of .25 km2 (Figures 4 and 5). The SG is elongated in NE–SW and N–S

directions and shows a mylonitic fabric defined by an approximately N–S-directed

mineral lineation and a N- and/or S-dipping foliation. Ductile deformation in the

SG gradually decreases toward higher elevations along the detachment surface in

the Menderes massif, and undeformed granodiorite outcrops are exposed at about

1500 m and higher.

The shear zone beneath the Alasehir detachment surface includes mylonitized

metamorphic and granitoid rocks that display well developed foliation and

stretching lineation in the lower sections and microbreaccia, breccia, cataclasite,

foliated cataclasite, and pseudotachylite toward the top (Figure 6; Isik et al. 2003;

Oner and Dilek 2007). The nearly 100-m-thick cataclastic shear zone beneath the

detachment surface contains S–C fabrics, microfaults, Riedel shears, and shear

bands, all consistently indicating top-to-the N–NE shearing (Oner and Dilek 2007).

The granitoid rocks become increasingly mylonitic upward into the detachment

shear zone. The mylonitic foliation in these rocks is defined by the alignment of

biotite and feldspar porphyclasts, and is subparallel to the detachment surface,

whereas the lineation is marked by stretched quartz and preferred orientations of

feldspar and biotite grains plunging to the N–NE (Figure 6; Isik et al. 2003; Oner

and Dilek 2007).

The intensity of the cataclastic deformation increases close to the Alasehir

detachment surface, wherein cataclastic features overprint the earlier ductile fabric

in the plutonic rocks. In the areas of lower elevation in the massif and across the

detachment surface, feldspar and quartz grains in the plutonic rocks are reduced in



size due to cataclastic deformation of the mylonitic rocks. The best exposures of the

mylonitic fabric and shear zone indicators in the SG are observed along the N–S-

trending stream valleys (e.g. Degirmendere Valley) crosscutting the Alasehir

detachment (Figure 4).

(a)

(b)

Figure 3. Field photos showing the Alasehir detachment and the overlying basinal strata.(a) The Neogene units in the Alasehir supradetachment basin and major north-dippingnormal faults in them. The modern Alasehir graben and its northern shoulder are seen in thebackground. View to the north. (b) Gently N-dipping slope in the background marks theAlasehir detachment surface, overlain by the upper Miocene Acidere Formation. The surfacein the foreground shows the cataclastic zone of the detachment surface. View to the east.

6 Z. Oner et al.


Detailed field geology and petrographic study of the deformed SG rocks indicate

that they can be categorized into two main groups, mylonitic and cataclastic, based

on their dynamic deformation patterns observed in hand specimens and thin-

sections. The mylonitic granitoids range from ultramylonites to protomylonites, and

exhibit ductile deformation structures.

Gently north-dipping (,20–30u) mylonitic foliation planes mostly strike WNW–

ENE and are defined by the alignment of dynamically recrystallized quartz, feldspar

and biotite porphyroclasts. The dip direction of the mylonitic foliation planes locally

changes to SE or SW due to back-tilting along small-scale extensional normal faults

or horizontal rotations along NNE–SSW-striking scissor faults (Figure 4). Mineral

lineation is mostly defined by the ,NE–SW-trending, NNE-plunging stretched

quartz and feldspar grains (Figure 6).

Kinematic indicators in the mylonitic rocks of the SG and the host metamorphic

rocks include S–C fabrics, asymmetric porphyroclasts, biotite fish, fractured and

displaced grains, and asymmetric enclaves that consistently show top-to-the N–NE

normal sense of shearing (Isik et al. 2003; Oner and Dilek 2007). The similar

orientation of the mylonitic foliation and stretching lineation, the same top-to-the

N–NE normal shear sense (Figure 6), and a corresponding retrograde greenschist-

facies metamorphic overprint in both the deformed granitoid and its host

metamorphic rocks indicate that the SG and the Menderes metamorphic rocks

Figure 4. Geological map of the SG, Menderes metamorphic massif, and the late CenozoicAlasehir basin strata. Lines AA9 through DD0 show the profile directions for geological cross-sections in Figure 5.



were affected by the same extensional deformation. The progression from relatively

undeformed isotropic granodiorite at depth to mylonitic-ultramylonitic plutonic

rocks within the detachment shear zone at the surface (Figure 5) further shows that

the SG pluton is a synextensional intrusion (Hetzel et al. 1995; Isik et al. 2003; Oner

and Dilek 2007).

In thin-sections of mylonitic granitoid rocks, the compositional layering defined

by alternating bands of chlorite + biotite + epidote ¡ quartz ribbons, quartz ¡

epidote ¡ chlorite ribbons, and feldspar ¡ biotite is a dominant structure

(Figure 7). Feldspar grain-size reduction is ubiquitious. Although plagioclase

crystals are commonly replaced (.50%) by an epidote–sericite–calcite assemblage,

vestiges of magmatic zoning in plagioclase are elongated within the foliation plane,

and locally some porphyroclasts have pressure shadows whose long axes are

assumed to present the average orientation of the x axis of the last incremental strain

ellipsoid and hence the direction of maximum elongation. This direction lies within

S surfaces of the initial mylonitic deformation that generally dips to the N–NW

(Figure 7). Quartz grains form typical s- and d-type porphyroclasts (Simpson and

Schmidt 1984; Hanmer and Passchier 1991), which show undulose extinction and

nascent recrystallization locally associated with core-and-mantle structures (White

1976).

Some samples exhibit s- and d-type asymmetric feldspar porphyroclasts with or

without stair-stepping and mantle-core structures in a matrix composed of biotite

(a)

(b)

(c)

(d )

Figure 5. Geological cross-sections showing the structural relations between the Salihlipluton, its host metamorphic rocks, the cataclastic zone of the detachment fault, and theupper Miocene-Pleistocene supradetachment sedimentary strata.

8 Z. Oner et al.


and/or recrystallized quartz grains. Some feldspar porphyroclasts with deformed

zoning patterns are surrounded by isolated quartz ribbons that are aligned parallel

to the mylonitic foliation (Figure 7) and by elongated, finer-grained, recrystallized

feldspar crystals. Myrmekite development in some samples represents another

kinematic indicator that is a breakdown product of K-feldspars during progressive

deformation (Figure 8; Simpson and Wintsch 1989). Deformation bands are

common in mylonitic granitoid samples. Grain boundary migration process has

resulted in dynamic recrystallization of biotite sub-grains with highly irregular

boundaries.

Grain-size reduction and dynamic recrystallization are the most common

deformational mechanisms controlling the inner texture of the mylonitic granitoid

samples, which were collected from different elevations along the detachment fault.

The moderately deformed mylonitic samples exhibit a porphyroclastic texture that

formed by breakage and fracturing of K-feldspar, plagioclase, and quartz grains

(Figure 9). The biotite grains are generally bent and kinked, and they flow around

the feldspar porphyroclasts parallel to the mylonitic foliation (Figures 7 and 9).

At the lower surface elevations along the Alasehir shear zone, ultramylonitic

rocks can be observed in a gradual or sharp contact with the mylonitic granitoid

rocks. Ultramylonites display a strong foliation characterized by rounded

porphyroclasts in a finer grain-sized matrix, which includes alternations of quartz,

feldspar and biotite bands (Figure 10). Shear indicators in these ultramylonites

display generally top-to-the north-northeast shearing and slip. In the field, ultra-thin

layers of pseudotachylite formation are also observed along some discrete shear

planes that occur parallel to the main Alasehir shear zone.

(a) (b)

(c) (d )

Figure 6. Field occurrences of the cataclastic breccia (a), proto-mylonitic (b), mylonitic (c),and ultra-mylonitic (d) granitoids. See text for explanation.



The protomylonitic rocks become predominant at structurally higher levels of the

Alasehir shear zone, whereby recrystallized quartz, feldspar and biotite grains occur

among the fractured igneous minerals of the granitoid rocks. Farther south and at

topographically higher elevations (,.1500 m), the protomylonitic fabric gradually

disappears and undeformed granitoid rocks crops out beneath the detachment

surface.

Figure 7. Photomicrograph of a mylonitic granitoid. B: biotite, F: feldspar, Q: quartz.

10 Z. Oner et al.


The second group of rocks is represented by the cataclastic rocks deformed in the

brittle–ductile regime. In these rocks, the mylonitic fabric is overprinted by brittle

and cataclastic structures (i.e. cataclasite, foliated cataclasite, breccia, and

microbreccia) that formed within the Alasehir shear zone. The alteration of

cataclastic rocks is mostly characterized by brownish colour in the field. Fresh

samples display dark blue to greenish colour in hand sample. In the cataclastic

samples, plagioclase, K-feldspar, and quartz grains are relatively strong and

commonly remain as relatively large relict crystals, whose edges and corners are

broken (Figure 11). The gently north-dipping cataclastic foliation can be seen as

mostly sub-parallel to the detachment fault. Intense fracturing and the formation of

systematic joints are very common brittle deformational features in the cataclastic

rocks. Very fine-grained, subhedral pyrite grains indicate hydrothermal alteration of

the cataclasites at the uppermost part of the Alasehir shear zone. Chlorite, sericite,

epidote, and calcite are also common alteration products in the cataclastic zone. In

thin-sections, angular to subrounded quartz, feldspar, and bitotite grains exhibit

undulose extinction, kinking, twinning, elongation, and they all occur in a fine-

grained matrix that is composed of rock fragments, dynamically recrystallized

quartz, biotite, and feldspar grains.

Brittle deformation of the SG

Both high-grade metamorphic rocks of the Menderes massif and the mylonitic

granitoid rocks of the Salihli pluton have been overprinted by late-stage, extensional

brittle shear zones and faults. Although the majority of these faults generally dip to

the north (Figure 12), south-dipping normal faults both in the granitoid rocks and

the cataclastic zone are not uncommon (Figure 13). The dip angles of the faults

range from 10–15u to .85u, but more steeply dipping faults commonly appear to

crosscut the gently dipping faults (Figure 12). These late-stage normal faults are

associated with damage zones that are generally few cm to .1 m in width. Thin and

irregular aplitic dikes occur along some of these faults and are commonly cut and

displaced along them in the outcrop.

Figure 8. Photomicrograph of a myrmekitic texture in a mylonitic granitoid. F: feldspar, Q:quartz.



Age of the SG

The geochronology of both the Salihli and Turgutlu granitoids and their

metamorphic host rocks provide significant constraints on the timing of the

extensional deformation and the synchronous magmatism in the footwall of the

central Menderes massif. Hetzel et al. (1995) obtained an amphibole isochron age

(40Ar/39Ar) of 19.5¡1.4 Ma from igneous hornblendes in the SG. Igneous biotites

from the Turgutlu and Salihli granodiorites yielded 40Ar/39Ar cooling ages of

13.2¡0.2 Ma and 12.2¡0.4 Ma, respectively (Hetzel et al. 1995). U–Pb monazite

ages of 16.1¡0.2 Ma from the Turgutlu granitoid and U–Pb allanite ages of

15.0¡0.3 Ma from the Salihli granodiorite date the crystallization ages of these two

granitoid bodies as the early-middle Miocene (Glodny and Hetzel 2007). These

crystallization ages are close to the matrix monazite ages of 17¡5 Ma (Catlos and

Figure 9. Photomicrograph of a proto-mylonitic granitoid. B: biotite, F: feldspar, Q: quartz,Pl: plagioclase. + /2 depict up/down displacement of mineral grains along surfaces that runperpendicular to the thin-section plane.

12 Z. Oner et al.


Cemen 2005) from metamorphic rocks in the eastern part of the Alasehir

detachment that are interpreted to record tectonic extension. More recently,

Catlos et al. (2008) reported in situ Th–Pb ion microprobe monazite ages of

21.7¡4.5 Ma to 9.6¡1.6 Ma (¡1 s) from the Salihli and Turgutlu granitoids and

31.5¡2.7 to 22.8¡2.4 Ma (¡1 s) from garnet-bearing schists from the Bozdag

nappe. These new ages demonstrate an older exhumation history of the middle

crustal rocks and the synextensional Salihli and Turgutlu plutons in the central

Menderes massif, going back to the early Miocene and possibly to the Oligocene.

Geochemistry of the SG

Analytical techniques

Major and trace element analysis of a total of 35 representative samples were

performed using XRF and ICP in the Petrology Research Laboratory housed in the

Figure 10. Photomicrograph of an ultra-mylonitic granitoid. B: biotite, F: feldspar, Q: quartz.



Department of Geological Engineering at the University of Ankara (Turkey). The

results of these analyses are given in Table 1. Multi-element concentration was

determined by using polarized energy dispersive XRF. The spectrometer used in this

study was the Spectro XLAB 2000 PEDXRF, equipped with an Rh anode X-ray

tube and 0.5 mm Be side window. The detector of the spectrometer was Si (Li),

cooled by liquid N2, with a resolution of ,150 eV at Mn Ka, 5000 cps. The

spectrometer was calibrated with two standard rocks, G01-MA-N and K03-MRG-

1, Canadian Certified Reference Materials and Centre de Recherches Petrographiques

et Geochimiques (CRPG) of France, based on the certificated concentrations of the

Figure 11. Photomicrograph of a cataclastically deformed granitoid.

Figure 12. Extensional brittle shear zones and normal faults in the SG. Most faults coalesceforming an anastomosing network of generally north-dipping fault planes.

14 Z. Oner et al.


(a) (b)

(c) (d )

(e) ( f )

Figure 13. Equal area stereoplots of different fabric elements in the study area. (a) Alasehirdetachment surface (great circles) mainly as gently north-dipping planes. (b) Contour diagramof poles to bedding planes in the Neogene basinal strata. Beds are tilted to the south and aredipping into the detachment surface. (c) Late-stage brittle normal faults (great circles) in theSG rocks. (d) Contour diagram of poles to mylonitic foliation planes in the SG rocks. (e)Late-stage brittle normal faults (great circles) in the cataclastic shear zone. (f) Contourdiagram of poles to foliation planes in the cataclastic shear zone.



Table 1. Major and trace element compositions of selected rock samples from the SG, Menderes core complex, western Anatolia.

02DEG07 03DEG07 04DEG07 05DEG07 06DEG07 07DEG07 08DEG07 09DEG07 10DEG07 11DEG07 12DEG07 13DEG07

SiO2 70.25 68.43 67.45 69.17 67.77 67.87 68.58 69.08 65.85 65.08 63.92 66.51Al2O3 14.66 14.90 14.49 14.76 15.21 14.02 15.33 14.31 15.26 15.72 14.94 15.07Fe2O3 3.10 3.26 4.18 3.29 3.63 3.96 2.98 3.18 3.98 4.31 5.47 4.18MnO 0.06 0.06 0.07 0.06 0.07 0.07 0.06 0.06 0.07 0.07 0.13 0.08MgO 1.14 1.57 2.09 1.62 2.05 2.24 1.24 1.48 1.99 2.39 3.04 2.39CaO 2.77 3.77 3.93 2.91 4.00 3.84 2.56 3.43 4.23 4.11 5.02 4.16Na2O 3.04 3.58 3.04 4.27 3.18 4.33 4.05 3.67 3.40 3.50 2.83 3.01K2O 3.46 3.13 3.21 3.09 2.78 2.91 3.80 3.15 3.71 2.99 2.95 2.99TiO2 0.47 0.48 0.61 0.46 0.53 0.59 0.45 0.50 0.55 0.64 0.58 0.57P2O5 0.16 0.16 0.17 0.15 0.18 0.15 0.13 0.19 0.19 0.22 0.16 0.20LOI 0.82 0.57 0.64 0.15 0.53 0.63 0.75 0.82 0.86 0.82 0.85 0.72Total 99.93 99.92 99.87 99.93 99.92 100.61 99.93 99.87 100.08 99.85 99.89 99.88

Ba 625.80 633.90 511.50 556.10 531.30 396.10 607.60 597.50 474.50 477.60 472.80 608.60Sr 243.70 326.80 297.70 302.40 350.70 306.30 302.40 285.70 349.40 355.70 319.40 346.70Y 21.20 17.50 24.50 16.50 16.90 17.30 19.30 13.60 17.80 18.60 34.40 14.70Zr 197.30 193.20 205.30 203.30 203.80 170.50 154.40 202.90 218.00 227.50 173.60 210.50Co 44.90 37.70 41.10 59.20 63.10 44.90 50.40 41.90 50.00 42.60 47.60 46.10Zn 57.60 51.90 61.70 63.70 55.40 60.60 52.40 55.60 55.20 64.10 79.70 60.10Ga 20.90 18.60 20.70 19.80 18.50 20.30 20.50 19.50 21.40 22.00 18.80 20.90Ge 1.80 1.30 1.33 2.40 1.93 2.60 1.30 2.40 2.40 1.32 1.30 1.30Rb 139.90 110.00 121.10 112.70 92.20 122.30 120.40 95.60 110.50 105.00 111.70 101.50Nb 15.20 14.60 19.90 14.50 16.20 13.60 13.90 15.10 16.50 16.80 14.70 11.90Sn 4.50 5.40 5.60 4.60 4.20 6.00 6.50 1.20 5.00 3.50 5.40 3.40Cs 22.30 14.30 17.70 21.70 16.50 22.80 17.30 22.50 7.80 3.52 16.30 29.10La 78.30 53.30 60.00 73.00 80.70 43.10 37.70 74.90 41.60 18.90 42.80 96.50Ce 130.20 92.60 101.80 113.20 119.30 63.40 70.30 129.80 78.90 35.50 80.60 150.00Hf 2.80 2.90 4.20 2.90 3.00 3.10 3.00 2.80 3.20 3.30 4.70 3.50Ta 4.20 10.70 9.10 4.20 4.90 4.50 4.20 3.70 4.30 4.60 9.90 3.80Tl 2.30 2.70 2.50 1.40 2.40 1.30 1.30 1.90 1.10 1.70 1.40 1.70Pb 64.70 50.00 38.00 45.70 39.30 44.20 54.00 44.00 40.90 41.90 38.80 42.60Bi 1.70 0.90 0.90 1.10 1.10 0.90 0.70 0.70 0.70 1.20 1.20 0.50Th 14.20 13.70 15.30 17.70 14.10 9.00 11.40 13.40 15.40 14.20 9.50 13.00U 10.80 8.20 7.70 6.80 7.70 18.30 7.30 6.80 15.60 15.30 8.00 9.50

16

Z.

On

eret

al.


14DEG07 15DEG07 16DEG07 17DEG07 18DEG07 19DEG07 20DEG07 21DEG07 22DEG07 23DEG07 24DEG07 25DEG07

SiO2 67.66 68.29 67.06 67.67 66.62 69.58 69.86 69.44 68.40 69.47 71.52 66.48Al2O3 14.73 14.35 14.73 14.62 15.25 14.33 14.20 14.22 14.21 14.34 14.25 15.49Fe2O3 3.88 3.81 3.97 3.77 4.05 3.20 3.23 3.82 3.94 3.56 2.21 4.12MnO 0.07 0.07 0.07 0.06 0.07 0.06 0.06 0.06 0.08 0.06 0.05 0.07MgO 1.85 1.63 2.30 1.64 2.02 1.86 1.39 1.35 1.88 1.63 0.97 2.04CaO 3.46 3.97 4.03 3.59 4.13 3.04 3.12 3.14 3.79 3.62 2.97 3.95Na2O 3.14 2.69 3.01 3.20 3.42 3.01 3.21 3.07 3.06 2.79 3.25 3.28K2O 3.48 4.10 3.24 3.59 2.78 3.71 3.17 3.98 2.83 2.94 3.69 2.98TiO2 0.57 0.57 0.55 0.53 0.62 0.46 0.48 0.42 0.56 0.56 0.30 0.64P2O5 0.17 0.18 0.19 0.17 0.20 0.18 0.19 0.15 0.17 0.16 0.11 0.22LOI 0.85 0.86 0.73 0.95 0.71 0.93 0.94 0.91 0.94 0.79 0.82 0.62Total 99.87 100.51 99.89 99.80 99.88 100.35 99.85 100.57 99.87 99.93 100.14 99.89

Ba 624.50 639.50 581.90 686.90 481.90 995.50 555.90 652.40 454.40 487.20 534.00 609.90Sr 292.40 291.90 350.90 323.80 312.80 296.40 282.40 274.00 282.00 292.50 279.80 372.80Y 16.80 16.30 16.40 18.10 23.50 11.50 17.90 15.70 16.90 20.90 12.70 18.50Zr 184.80 214.30 212.80 191.30 217.40 207.20 222.70 172.60 196.60 206.30 131.40 222.20Co 37.20 41.00 44.30 30.60 64.70 46.00 45.00 29.30 32.50 39.40 52.00 45.20Zn 67.90 60.70 54.30 46.30 61.20 52.40 58.40 50.60 68.90 55.80 41.70 61.60Ga 21.70 20.70 20.40 19.10 21.00 21.50 21.90 20.80 21.30 18.10 19.60 21.60Ge 2.30 1.40 1.30 1.30 1.30 1.30 1.10 0.30 1.90 1.34 0.80 2.00Rb 135.40 139.20 97.90 95.80 91.00 113.30 104.80 144.20 120.10 121.10 102.00 101.00Nb 18.70 15.90 12.00 13.40 18.30 16.00 20.20 14.80 17.10 18.10 8.00 15.40Sn 3.10 4.10 3.90 3.20 4.10 0.90 2.00 4.30 10.10 3.90 3.50 4.10Cs 26.10 20.50 19.20 23.10 16.90 23.60 3.90 17.40 17.40 21.20 13.60 15.30La 61.00 39.00 78.50 117.50 65.70 79.30 8.50 62.20 44.10 39.60 42.10 60.90Ce 107.60 81.00 122.50 191.40 111.70 126.70 135.40 108.10 80.30 67.20 64.00 111.90Hf 4.60 3.80 2.50 3.10 3.10 3.00 2.90 3.20 3.30 3.10 3.10 3.30Ta 5.70 4.00 3.90 3.30 4.50 4.20 4.00 4.30 3.80 7.60 4.30 3.70Tl 1.40 1.10 2.40 1.70 1.90 1.40 1.20 2.30 1.60 1.70 1.60 1.00Pb 48.70 53.30 38.10 42.10 38.20 53.70 50.60 58.00 48.40 42.90 60.30 40.70Bi 0.40 0.70 1.50 0.80 1.60 0.60 1.00 0.90 1.00 1.10 2.00 1.00Th 10.40 10.80 12.90 10.30 15.60 12.10 10.30 14.40 13.50 8.90 8.10 13.80U 8.20 8.30 9.20 7.50 7.80 8.00 10.60 7.00 6.70 7.30 9.00 6.60

Table 1. (Continued.)

Intern

atio

na

lG

eolo

gy

Review

17


26DEG07 27DEG07 28DEG07 29DEG07 30DEG07 31DEG07 32DEG07 33DEG07 34DEG07 35DEG07 36DEG07

SiO2 67.48 66.25 65.92 66.96 71.66 67.34 67.10 66.21 66.48 73.95 67.17Al2O3 14.95 15.34 15.23 15.25 13.44 15.03 15.32 15.22 15.71 13.10 15.06Fe2O3 3.73 4.28 4.68 3.96 2.89 3.47 3.81 4.18 3.83 1.77 3.80MnO 0.06 0.07 0.08 0.07 0.06 0.07 0.07 0.07 0.06 0.03 0.07MgO 1.93 2.18 2.31 2.04 1.18 1.84 1.50 2.53 2.13 0.97 1.87CaO 3.68 4.19 4.54 4.10 2.69 3.88 3.76 3.66 3.41 2.96 4.01Na2O 3.20 3.27 2.85 3.34 2.86 3.34 4.22 3.43 3.51 2.75 3.78K2O 3.36 2.70 2.38 2.77 3.91 3.30 3.27 2.99 3.38 4.10 2.82TiO2 0.55 0.61 0.70 0.59 0.43 0.54 0.47 0.68 0.57 0.28 0.57P2O5 0.20 0.24 0.24 0.21 0.17 0.18 0.16 0.20 0.19 0.09 0.19LOI 0.76 0.69 0.82 0.62 0.65 0.90 0.72 0.68 0.62 0.34 0.54Total 99.91 99.82 99.76 99.91 99.94 99.89 100.40 99.85 99.89 100.35 99.88

Ba 777.90 511.10 620.00 607.30 564.80 731.00 601.00 460.80 618.30 376.30 481.80Sr 352.60 370.00 384.00 369.70 256.80 337.80 319.00 338.30 345.70 269.20 326.20Y 17.20 19.90 17.80 21.20 21.90 19.60 22.50 24.00 23.50 12.40 21.90Zr 202.60 218.00 239.40 231.70 154.60 196.90 188.40 215.80 193.30 103.40 223.90Co 41.80 12.00 28.70 41.70 58.70 59.00 42.80 45.40 56.70 46.60 39.70Zn 56.40 58.20 60.90 58.10 50.60 50.20 57.60 61.00 56.90 29.90 57.40Ga 20.30 21.40 19.40 19.60 20.20 19.80 19.50 20.00 21.10 15.80 21.20Ge 0.34 1.80 1.32 0.63 1.30 1.70 1.10 2.30 0.67 1.78 0.32Rb 102.30 93.70 70.40 86.20 132.70 103.70 108.90 108.00 116.00 85.60 95.30Nb 14.80 16.80 15.50 15.70 12.80 12.30 23.50 17.90 16.40 12.50 17.30Sn 1.70 2.90 5.00 4.70 4.00 3.20 6.90 7.60 1.00 1.00 4.40Cs 18.50 3.54 9.40 3.21 22.40 20.70 3.11 12.30 33.40 3.50 16.80La 73.70 10.90 64.30 11.30 59.50 68.40 20.30 47.10 103.00 7.40 69.10Ce 113.40 88.70 108.90 104.60 94.60 95.50 32.50 85.00 166.20 12.20 124.80Hf 3.30 4.50 3.20 3.00 3.00 3.10 3.20 4.30 3.00 2.80 3.30Ta 4.00 4.20 4.80 4.00 3.40 4.10 8.10 5.20 4.00 4.10 4.90Tl 1.80 1.10 1.10 1.60 1.20 1.50 2.20 1.80 1.50 1.50 1.50Pb 44.60 39.40 41.40 39.50 50.70 44.80 45.40 41.80 43.40 54.20 42.60Bi 1.00 1.40 1.30 1.10 1.70 1.00 1.10 1.20 0.80 0.80 1.20Th 12.60 13.00 12.50 15.10 12.30 10.50 16.20 12.30 11.60 14.90 15.50U 7.20 20.80 7.30 10.60 8.00 10.70 16.10 10.10 6.90 20.60 10.30

Table 1. (Continued.)

18

Z.

On

eret

al.


elements under investigation. The samples were ground into fine powder in an agate

mortar, passed through a 200 mm sieve, and then pressed into thick pellets of 32 mm

diameter using wax as binder. USGS standards, GEOL, GBW 7109 and GBW-7309

ediment were pressed into pellets in a similar manner as the samples, and these

standards were used for quality assurance (La Tour 1989; Johnson et al. 1999). Total

analysis time for each additional element was 30 min.

Major and trace element characteristics

On the total alkali versus silica (TAS) diagram the SG rocks plot in the

subalkaline field (Figure 14(a)), and follow a calc-alkaline trend on the AFM

diagram (Figure 14(b)) with a good linear trend. The majority of the samples

belong to the high-K calc-alkaline series on the SiO2 versus K2O diagram

(Figure 15(A)) and are metaluminous to slightly peraluminous as observed on an

A/CNK versus ANK diagram (Figure 15(b)). No peralkaline samples were

observed.

The silica contents of the SG samples range from 62.36 to 73.95 wt-%, and their

major element variations define linear trends as seen in Figure 16. The Fe2O3, TiO2,

MgO, CaO, Al2O3, and P2O5 contents decrease with increasing SiO2 on the Harker

diagrams, whereas the K2O and Na2O appear to increase with increasing SiO2

values although they sow some scatter. There is a negative correlation of Zr and Sr

with SiO2 contents indicating their depletion (Figure 16(b)).

Primitive mantle (PM)-normalized trace element patterns for the SG are given in

Figure 17. In general all subunits of the SG show enrichment in large-ion lithophile

elements (LILE) (K, Rb, Cs), depletion in high-field strength elements (HFSE)

relative to the primitive mantle, and strong negative anomalies in Ba, Nb, Sr, P, and

Ti. These geochemical characteristics are similar to the patterns of those rocks

formed at convergent margins (Wilson 1989; Cox 1983). Elemental patterns of upper

(UC) and lower continental crust (LC) are also plotted in Figure 17 for the purpose

of comparison. The SG samples appear to be more identical to the composition of

the upper crust rather than the lower crust, suggesting that the SG magmas in part

may have been derived from partial melting of the upper crust.

On the tectonic discrimination diagrams of Pearce (1984), all analysed SG samples

plot within the VAG (volcanic arc granite) and syn-COLG (syncollisional granite)

fields in the Nb versus Y diagram and within the post-COLG (post-collisional

granite) field (Figure 18). This inferred range of the SG magmas suggests a complex

tectonomagmatic history of the granitoid rocks.

Petrogenesis of the SG

The A/CNK molecular ratios of the SG rocks between 0.81 and 1.27 (Figure 15(B))

indicate that these plutons are predominantly metaluminous, I-type granitoids and

slightly peraluminous, rare S-type, two-mica granitoids (White and Chappell 1977;

Chappell and White 1992). The SG samples have trace elemental patterns similar to

those of the upper continental crust (Figure 17) suggesting inheritance from crustal

melts of variable sources and compositions.

The PM-normalized multi-element patterns of the intermediate rocks of the SG

show enrichment in Rb, Th, and K, and negative anomalies in Ba, Sr, P, and Ti.

These patterns suggest derivation of the rocks from basaltic magmas through crystal

fractionation. The observed linear and continuous variations in the Harker



diagrams (Figure 16) indicate that fractional crystallization was an important

process during evolution of the SG magmas. The negative covariances between SiO2

and FeO* (FeO + Fe2O3), MgO, and CaO (Figure 16(a)) suggest fractionation of

(a)

(b)

Figure 14. (a) Alkali versus silica diagram for the SG samples (alkaline – subalkalinedivision is from Irvine and Baragar 1971). (b) AFM diagram for the SG samples (tholeiitic –calc-alkaline division is from Irvine and Baragar 1971).

20 Z. Oner et al.


olivine and clinopyroxene during the evolution of the SG magmas. Variations in

CaO with silica are almost the same in all groups. Decreasing CaO with increasing

silica indicates that Ca-rich phases such as hornblende and Ca-plag were

progressively removed from the granitic melt. The increasing Rb and decreasing

Sr contents of the SG with increasing SiO2 (Figure 16(b)) indicating significant

feldspar fractionation during the evolution of the SG. These inferred magma

fractionation processes necessitate either voluminous parental magma for the SG

and other plutons (Alasehir and Turgutlu) in the Menderes massif, or derivation of

magmas by partial melting of a mafic source (i.e. amphibolite) in the middle to lower

continental crust. However, the occurrence of coeval mafic intrusions and extrusive

rocks has not been documented from the Menderes massif, as would be expected

from the processes involved in these models.

Trace element patterns of the SG samples are consistent with derivation of their

magmas from an incompatible element-enriched source, as evidenced by negative

Nb anomalies, enriched LREE, and low Rb/Sr ratios. These features of the SG

Figure 15. (a) SiO2 versus K2O diagram for the SG samples (calc-alkaline – shoshoniticdivision is from Rickwood 1989). (b) The Shand’s index diagram for the SG samples (Shand1927). A/CNK: molar Al2O3/(CaO + Na2O + K2O); A/NK: molar Al2O3/(Na2O + K2O).



22 Z. Oner et al.


Figure 16. Selected major element in wt-% (a) and trace-element in ppm (b) variationdiagrams for the SG samples.



plutons are similar to those of igneous rocks formed at convergent margins (Thorpe

et al. 1982; Davidson et al. 1991; Pearce and Peate 1995). High incompatible element

abundances (e.g. K, Rb, Nb, and Ba) and inter-element relationships (e.g. Ce/Y, Zr/

Ba, Th/Yb, and Ba/Nb ratios) of the SG rocks indicate a subduction-enriched,

heterogeneous sub-continental lithospheric mantle source (cf. McCulloch and

Gamble 1991; McDonough 1990; Thirlwall et al. 1994; Pearce and Peate 1995;

Pearce et al. 1990).

We infer that the subduction-related enrichment of the western Anatolian

lithospheric mantle was likely inherited from earlier convergent margin events.

Source enrichment through previous subduction events in the region has been

suggested by some authors for the Cenozoic plutonism and related volcanism in

western Anatolia (Seyitoglu et al. 1997; Genc and Yilmaz 1997; Yilmaz and Polat

Figure 17. Primitive mantle (PM) – normalized trace element patterns for the SG samples.Normalizing factors after Sun and McDonough (1989).

24 Z. Oner et al.


1998; Altunkaynak and Yilmaz 1998; Yilmaz et al. 2000, 2001; Aldanmaz et al.

2000; Koprubasi and Aldanmaz 2004; Altunkaynak and Dilek 2006; Altunkaynak

2007; Dilek and Altunkaynak 2007). The important question is the nature of the

heat source, which triggered partial melting of the subduction-modified mantle

lithosphere beneath the western Anatolian region during the Oligo-Miocene.

Regional studies of the late Cenozoic, synextensional plutons in western Anatolia

and the Aegean Islands have shown that these intrusions have high positive eNd(t)

and low initial 87Sr/86Sr ratios (Juteau et al. 1986; Pe-Piper and Piper 2001; Altherr

and Siebel 2002; Dilek and Altunkaynak 2007; Aydogan et al. 2008). These isotopic

values indicate a strong fingerprint of mantle-derived basaltic magmas in their

petrogenetic evolution. The granitic magmas of these plutons were an end-point of

Figure 18. Trace element tectonic discrimination diagrams of the SG samples. VAG:volcanic arc granites, WPG: within plate granites, ORG: ocean ridge granites, COLG:collisional granites, syncollision granites. (Fields after Pearce 1984) (a) Nb versus Y (in ppm)diagram; (b) Rb versus Y + Nb (in ppm) diagram.



melting of metasomatized lithospheric mantle and lower crustal material injected by

basaltic magmas of an asthenospheric source. Dilek and Altunkaynak (2008) have

suggested that slab rollback-induced lithospheric delamination beneath the Aegean

region in the early Miocene caused asthenospheric upwelling, which in turn led to

melting of the subduction-enriched lithospheric mantle. Invasion of the lower and

middle crust by lithospheric mantle-derived melts triggered MASH-type processes

(melting, assimilation, storage, homogenization; Hildreth and Moorbath 1988),

resulting in the production of hybrid magmas of the SG (Figure 19(a)). These hybrid

magmas were further affected by crustal contamination in shallow-level magma

chambers in the upper crust. Both lithospheric mantle and crustal melts were

therefore involved in the evolution of the SG plutons.

Figure 19. Tectonic evolution of the Menderes core complex and its synextensionalmagmatism. (a) Schematic cross-section, depicting the inferred tectonomagmatic evolutionof the Menderes metamorphic dome and hybrid magmatism in the lithospheric mantle andlower to upper crust during the middle Miocene. (b) Emplacement of the Salihli and othergranitoid(s) in the middle crust and their progressive unroofing with continued extensionthrough time. Notice the inferred , 10 km of crustal thinning by the time the granitoidplutons were exposed at the surface in the middle to late Miocene. (c) Development of high-angle normal faults in the late Miocene, forming graben structures and crosscutting thedetachment surfaces and the earlier extensional deformational fabrics in the granitoid plutonsand their metamorphic host rocks. This late-stage brittle deformation caused uplifting of thegraben shoulders and further exhumation of the detachment footwalls. (d–f) Progressiveevolution of the supradetachment basin and its Neogene strata on the Alasehir detachment.See text for further discussion.

26 Z. Oner et al.


Synextensional tectonics of the SG

Contact relations of the SG with its metamorphic host rocks and the synextensional

deformation patterns both in the granitoid and high-grade metamorphic rocks

indicate that the SG pluton was intruded into already mylonitized metamorphic

rocks. Considering the early Miocene (,21.7–16.1 Ma) ages of the SG and Turgutlu

plutons, these observations and interpretations suggest that crustal extension and

associated doming in the Menderes massif was already underway by this time

(Figure 19(b)). Glodny and Hetzel (2007) estimated a minimum amount of

exhumation of 7.5 km since c. 13–12 Ma, using a regional geothermal gradient of

,40uC/km and the temperature value of 300uC for Ar-isotopic closure of igneous

biotites (as found in the SG rocks). They suggested that through a combination of

tectonic extension, uplift, and erosion, nearly 10–15 km of overburden has been

removed from the Menderes massif during the last 15–16 million years. If we

consider the oldest possible extensional ages of 36¡2 Ma for the Menderes massif,

as suggested by Lips et al. (2001) based on 40Ar/39Ar white mica ages from

extensional deformation fabrics in the Menderes metamorphic rocks, the amount of

this removal would be even higher. These estimates collectively suggest that the SG

and other plutons in the Menderes core complex were originally emplaced in upper

to middle crustal levels, and that they were then subsequently brought up to the

surface via extensional exhumation and denudation (Figure 19(b)).

Whether the crustal extension in the Menderes core complex was continuous since

at least 16 Ma (Hetzel et al. 1995; Emre 1996) or was punctuated by short-lived

contractional episode(s) (Kocyigit et al. 1999; Gokten et al. 2001; Bozkurt 2003) has

been a subject of debate. However, recent geochronological and thermochronolo-

gical data clearly show that extensional deformation fabrics continued to form in the

late Miocene (Lips et al. 2001; Catlos and Cemen 2005), and that the final cooling of

the Menderes metamorphic rocks and the Salihli and Turgutlu granitoids may have

occurred as recently as 1.9¡0.4 Ma (Gessner et al. 2001b). Our own field

observations within the lower Miocene and younger sedimentary strata in the

Alasehir supradetachment basin do not support the presence of any late Miocene

contractional folds in these rocks (Oner and Dilek 2007).

Sufficient cooling of the exhumed mid- to lower-crustal rocks (including the SG

pluton) in the Menderes core complex was followed around 7¡1 Ma by the

development of high-angle normal faults forming graben structures (Figure 19(c);

Hetzel et al. 1995, 1998; Gessner et al. 2001a; Lips et al. 2001). These faults crosscut

the low-angle detachment surfaces and the earlier extensional deformational fabrics

in the granitoid plutons and their metamorphic host rocks (Figure 19(c)).This late-

stage normal faulting caused relative uplifting of the graben shoulders and further

exhumation of the detachment footwalls. The SG pluton continued to be deformed

cataclastically and brittly during this phase as it was further uplifted tectonically

together with its metamorphic host rocks.

The extensional deformation of the Menderes core complex and its synextensional

granitoid plutons in the footwalls of the north-dipping Alasehir and the south-

dipping Buyuk Menderes detachments was accompanied by the formation of

asymmetric supradetachment basins in their hanging walls (Figure 19(c)). The oldest

sedimentary rocks overlying the Alasehir detachment surface are the middle

Miocene lacustrine shale-limestone units of the Gerentas and Kaypaktepe units

(Figure 19(d)). The continued uplift of the Menderes massif provided the necessary

relief and detrital material for the fluvial and alluvial fan systems in the Alasehir



supradetachment basin, now represented by the Acidere and Gobekli units

(Figure 19(e)); Oner and Dilek 2008). The upper Miocene fluvial and alluvial fan

deposits unconformably overlying these units represent a surge of clastic deposition

along the northern edge of the core complex associated with the onset of range-front

faulting in the Menderes massif by the late Miocene. A combination of rotational normal

and scissor faulting in the extending Alasehir basin affected the depositional patterns and

produced local unconformities within the basinal strata. High-angle, oblique-slip scissor

faults crosscutting the Menderes massif, the detachment surface, and the basinal rocks

caused differential uplift, producing fault blocks with different structural architecture

and metamorphic grades. This fault kinematics and the distribution of range-parallel

and range-perpendicular faults strongly controlled the shape and depth of the

accommodation space and the structural orientation and architecture of the sedimentary

strata within the Alasehir supradetachment basin (Oner and Dilek 2008). These Neogene

rocks mostly display moderately to steeply south-dipping layers in present time as a

result of extensional rotation along these late-stage normal faults (Figure 19(F)).

Conclusions

N The early Miocene SG in the Menderes metamorphic core complex in western

Anatolia is a synextensional intrusion, which was unroofed from mid-crustal

levels together with its host metamorphic rocks in the footwall of the Alasehir

detachment fault.

N The strong mylonitic fabric defined by a generally N-dipping foliation and a

,N-S-directed mineral lineation in the NE–SW elongated SG beneath the

Alasehir detachment shear zone is a result of ductile deformation that

developed during its exhumation. The Alasehir detachment shear zone includes

cataclastic features, represented by microbreaccia, breccia, cataclasite, foliated

cataclasite, and pseudotachylite that overprint the earlier ductile fabric in the

plutonic rocks. All these structures are crosscut by younger, brittle normal

faults that propagate into the overlying lower-middle Miocene sedimentary

strata in the Alasehir supradetachment basin.

N Compositionally, the SG is made of granite, granodiorite, alkali-feldspar

granite, monzogranite, and syenogranite that are metaluminous to slightly

peraluminous, high-K calc-alkaline rocks. Enrichment of these rocks in LILE

and depletion in HFSE, and their strong negative anomalies in Ba, Nb, Sr, P,

and Ti are characteristic of plutons formed at convergent margins.

N The compositional variations of the synextensional SG are an artifact of

different degrees of partial melting of a mixed source including varying

proportions of a subduction-metasomatized and enriched lithospheric mantle

component and assimilated-melted middle to upper crustal components.

N The heat source for partial melting of the subduction-metasomatized

lithospheric mantle and the overlying crust for the generation of the SG

magmas was provided by asthenospheric upwelling induced by lithospheric

delamination beneath the Aegean region. This inferred lithospheric delamina-

tion was triggered by peeling of the base of the subcontinental lithosphere as a

result of the rapid slab retreat of the Hellenic subduction zone.

Acknowledgements

This study is part of Z. Oner’s doctoral dissertation work at Miami University and

has been funded in part by research grants from the Geological Society of America,

28 Z. Oner et al.


American Association of Petroleum Geologists (AAPG) Foundation Grants-in-Aid

Program, Sigma Xi The Scientific Research Society, and the Department of Geology

at Miami. Logistical help and access to the laboratory facilities in the Department of

Geological Engineering at the University of Istanbul during the course of Z. Oner’s

fieldwork in Turkey are greatly appreciated. Constructive and thorough reviews by

Paul Robinson and Andor Lips helped us improve the paper.

ReferencesAgostini, S., Doglioni, C., Innocenti, F., Manetti, P., Tonarini, S., and Savascin, M.Y., 2007,

The transition from subduction-related to intraplate Neogene magmatism in the western

Anatolia and Aegean area, in Beccaluva, L., Bianchini, G., and Wilson, M., eds.,

Cenozoic volcanism in the Mediterranean area: Geological Society of America Special

Paper, v. 418, p. 1–15.

Akay, E., 2008, Geology and petrology of the Simav Magmatic Complex (NW Anatolia) and

its comparison with the Oligo-Miocene granitoids in NW Anatolia: implications on

Tertiary tectonic evolution of the region: International Journal of Earth Sciences: DOI:

10.1007/s00531-008-0325-0.

Akay, E., and Erdogan, B., 2004, Evolution of calc-alkaline to alkaline volcanism in the Aliaga-

Foca region (Western Anatolia, Turkey): Journal of Asian Earth Sciences, v. 24, p. 367–387.

Aldanmaz, E., Pearce, J., Thirwall, M.F., and Mitchell, J., 2000, Petrogenetic evolution of late

Cenozoic, post-collision volcanism in western Anatolia, Turkey: Journal of Volcanology

and Geothermal Research, v. 102, p. 67–95.

Altherr, R., Henjes-Kunst, F.J., Matthews, A., Firedrichsen, H., and Hansen, B.T., 1988, O–

Sr isotopic variations in Miocene granitoids from the Aegean: evidence for an origin by

combined assimilation and fractional crystallization: Contributions to Mineralogy and

Petrology, v. 100, p. 528–541.

Altherr, R., and Siebel, W., 2002, I-type plutonism in a continental back-arc setting: Miocene

granitoids and monzonites from the central Aegean Sea, Greece: Contributions to

Mineralogy and Petrology, v. 143, p. 397–415.

Altunkaynak, S., 2007, Collision-driven slab breakoff magmatism in Northwestern Anatolia,

Turkey: Journal of Geology, v. 115, p. 63–82.

Altunkaynak, S., and Yilmaz, Y., 1998, The Mount Kozak magmatic complex, Western

Anatolia: Journal of Volcanology and Geothermal Research, v. 85, p. 211–131.

Altunkaynak, S., and Dilek, Y., 2006, Timing and nature of postcollisional volcanism in

western Anatolia and geodynamic implications, in Dilek, Y., and Pavlides, S., eds.,

Postcollisional tectonics and magmatism in the Mediterranean region and Asia:

Geological Society of America Special Paper, v. 409, p. 321–351.

Aydogan, M.S., Coban, H., Bozcu, M., and Akinci, O., 2008, Geochemical and mantle-like

isotopic (Nd, Sr) composition of the Baklan Granite from the Muratdagı Region

(Banaz, Usak), western Turkey: Implications for input of juvenile magmas in the source

domains of western Anatolia Eocene–Miocene granites: Journal of Asian Earth

Sciences, v. 33, p. 155–176.

Bozkurt, E., 2003, Origin of NE-trending basins in western Turkey: Geodinamica Acta, v. 16,

p. 61–81.

———, 2004, Granitoid rocks of the southern Menderes Massif (Southwest Turkey): field

evidence for Tertiary magmatism in an extensional shear zone: International Journal of

Earth Sciences, v. 93, p. 52–71.

Bozkurt, E., and Park, R.G., 1994, Southern Menderes Massif: an incipient metamorphic

core complex in western Anatolia, Turkey: Journal of the Geological Society, London,

v. 151, p. 213–216.

Bozkurt, E., and Satir, M., 2000, The southern Menderes Massif (western Turkey):

geochronology and exhumation history: Geological Journal, v. 35, p. 285–296.



Bozkurt, E., and Oberhansli, R., 2001, Menderes Massif (Western Turkey): Structural,

metamorphic and magmatic evolution – a synthesis: International Journal of Earth

Sciences, v. 89, p. 679–708.

Candan, O., Dora, O.O., Oberhansli, R., Cetinkaplan, M., Partzch, J.H., Warkus, F.C., and

Durr, S., 2001, Pan-African high-pressure metamorphism in the Precambrian basement

of the Menderes massif, western Anatolia, Turkey: International Journal of Earth

Sciences, v. 89, p. 793–811.

Candan, O., Cetinkaplan, M., Oberhansli, R., Rimmele, G., and Akal, C., 2005, Alpine high-

P/low-T metamorphism of the Afyon Zone and implications for the metamorphic

evolution of Western Anatolia, Turkey: Lithos, v. 84, p. 102–124.

Catlos, E.J., and Cemen, I., 2005, Monazite ages and the evolution of the Menderes Massif,

western Turkey: International Journal of Earth Sciences, v. 94, p. 204–217.

Catlos, E.J., Cemen, I., Isik, V., and Seyitoglu, G., 2002, In situ timing constraints from the

Menderes massif, western Turkey: Geological Society of America Abstracts with

Programs, v. 34, no. 6, 180 p.

Catlos, E.J., Baker, C., Sorensen, S.S., Cemen, I., and Hancer, M., 2008, Monazite

geochronology, magmatism, and extensional dynamics within the Menderes massif,

Western Turkey: Donald Harrington Symposium on the Geology of the Aegean, IOP

Conference Series, Earth and Environmental Science, v. 2, 012013.

Chappell, B.W., and White, A.J.R., 1992, I- and S-type granites in the Lachlan fold belt:

Transactions of the Royal Society of Edinburgh Earth Sciences, v. 83, p. 1–16.

Cox, K., and Keller, J., 1983, Primary magmas and their evolution, in Proceedings, 2nd

Meeting of the European Union of Geosicences, Terra Cognita, v. 4, 44 p.

Davidson, J.P., Harmon, R.S., and Worner, G., 1991, The source of central Andean magmas:

some considerations, in Harmon, R.S., and Rapela, C.W., eds., Andean Magmatism

and its Tectonic Setting, Geological Society of America Special Paper, v. 265,

p. 233–243.

Dilek, Y., 2006, Collision tectonics of the Mediterranean region: causes and consequences, in

Dilek, Y., and Pavlides, S., eds., Postcollisional tectonics and magmatism in the

Mediterranean region and Asia, Geological Society of America Special Paper, v. 409,

p. 1–13.

Dilek, Y., and Whitney, D.L., 2000, Cenozoic crustal evolution in central Anatolia:

Extension, magmatism and landscape development, in Panayides, I., Xenophontos, C.,

and Malpas, J., eds., Proceedings, Third International Conference on the Geology of the

Eastern Mediterranean, Nicosia, September 1998: Nicosia, Geological Survey

Department, p. 183–192.

Dilek, Y., and Altunkaynak, S., 2007, Cenozoic crustal evolution and mantle dynamics of

post-collisional magmatism in western Anatolia: International Geology Review, v. 49,

p. 431–453.

———, 2008, Geochemical and temporal evolution of Cenozoic magmatism in western

Turkey: Mantle response to collision, slab breakoff, and lithospheric tearing in an

orogenic belt, in Van Hinsbergen, D.J.J., Edwards, M.A., and Govers, R., eds.,

Collision and Collapse at the Africa-Arabia-Eurasia Subduction Zone. Geological

Society of London Special Publications, v. 311, p. 213–233.

Emre, T., 1996, Gediz Grabeni’nin jeolojisi ve tektonigi: Turkish Journal of Earth Sciences,

v. 5, p. 171–185.

Genc, S.C., and Yilmaz, Y., 1997, An example of post-collisional magmatism in northwestern

Anatolia: the Kizderbent Volcanics (Armutlu Peninsula, Turkey): Turkish Journal of


Gessner, K., Collins, A.S., Ring, U., and Gungor, T., 2004, Structural and thermal history of

poly-orogenic basement: U–Pb geochronology of granitoid rocks in the southern

Menderes massif, western Turkey: Journal of Geological Society London, v. 161,

p. 93–101.

30 Z. Oner et al.


Gessner, K., Piazolo, S., Gungor, T., Ring, U., Kroner, A., and Passchier, C.W., 2001a,

Tectonic significance of deformation patterns in granitoid rocks of the Menderes

nappes, Anatolide belt, southwest Turkey: International Journal of Earth Sciences,

v. 89, p. 766–780.

Gessner, K., Ring, U., Johnson, C., Hetzel, R., Passchier, C.W., and Gungor, T., 2001b, An

active bidivergent rolling-hinge detachment system: The central Menderes metamorphic

core complex in western Turkey: Geology, v. 29, p. 611–614.

Glodny, J., and Hetzel, R., 2007, Precise U–Pb ages of syn-extensional Miocene intrusions

in the central Menderes Massif, western Turkey: Geological Magazine, v. 144,

p. 235–246.

Gokten, E., Havzaoglu, S., and San, O., 2001, Tertiary evolution of the central Menderes

Massif based on structural investigations of metamorphics and sedimentary cover rocks

between Salihli and Kiraz (western Turkey): International Journal of Earth Sciences,

v. 89, p. 745–756.

Hanmer, S., and Passchier, C., 1991, Shear-sense indicators: a review: Geological Survey of

Canada Paper, v. 90, 17 p.

Hetzel, R., Ring, U., Akal, C., and Troesch, M., 1995, Miocene NNE-directed extensional

unroofing in the Menderes massif, western Turkey: Journal of the Geological Society,

London, v. 152, p. 639–654.

Hetzel, R., Romer, R.L., Candan, O., and Passcheir, C.W., 1998, Geology of the Bozdag

area, central Menderes massif, SW Turkey: Pan-African basement and Alpine

deformation: Geologische Rundschau, v. 87, p. 394–406.

Hildreth, W., and Moorbath, S., 1988, Crustal contributions to arc magmatism in the Andes

of central Chile: Contributions to Mineralogy and Petrology, v. 98, p. 455–489.

Innocenti, F., Agostini, S., Di Vincenzo, G., Doglioni, C., Manetti, P., Savascin, M.Y., and

Tonarini, S., 2005, Neogene and Quaternary volcanism in Western Anatolia: Magma

sources and geodynamic evolution: Marine Geology, v. 221, p. 397–421.

Irvine, T.N., and Baragar, W.R.A., 1971, A guide to the chemical classification of common

volcanic rocks: Canadian Journal of Earth Science, v. 8, p. 523–548.

Isik, V., Seyitoglu, G., and Cemen, I., 2003, Ductile–brittle transition along the Alasehir

detachment fault and its structural relationship with the Simav detachment fault,

Menderes massif, western Turkey: Tectonophysics, v. 374, p. 1–18.

Isik, V., Tekeli, O., and Seyitoglu, G., 2004, The 40Ar/39Ar age of extensional ductile

deformation and granitoid intrusion in the northern Menderes core complex:

implications for the initiation of extensional tectonics in western Turkey: Journal of

Asian Earth Sciences, v. 23, p. 555–566.

Johnson, D.M., Hooper, P.R., and Conrey, R.M., 1999, XRF Analysis of Rocks and

Minerals for Major and Trace Elements on a Single Low Dilution Li-tetraborate Fused

Bead: International Centre for Diffraction Data, v. 41, p. 843–867.

Juteau, M., Michard, A., and Albarede, F., 1986, The Pb–Sr–Nd isotope geochemistry of

some recent circum-Mediterranean granites: Contributions to Mineralogy and

Petrology, v. 92, p. 331–340.

Kocyigit, A., Yusufoglu, H., and Bozkurt, E., 1999, Evidence from the Gediz graben for

episodic two-stage extension in western Turkey: Journal of the Geological Society of

London, v. 156, p. 605–616.

Koprubasi, N., and Aldanmaz, E., 2004, Geochemical constraints on the petrogenesis of

Cenozoic I-type granitoids in Northwest Anatolia, Turkey: Evidence for magma

generation by lithospheric delamination in a post-collisional setting: International

Geology Review, v. 46, p. 705–729.

La Tour, T.E., 1989, Analysis of Rocks using X-Ray Fluorescence Spectrometry: The Rigaku

Journal, v. 6, no. 1, p. 3–9.

Lips, A.L.W., Cassard, D., Sozbilir, H., Yilmaz, H., and Wijbrans, J.R., 2001, Multistage

exhumation of the Menderes Massif, western Anatolia (Turkey): International Journal

of Earth Sciences, v. 89, p. 781–792.



Loos, S., and Rischmann, T., 1999, The evolution of the southern Menderes Massif in SW

Turkey as revealed by zircon dating: Journal of the Geological Society, London, v. 156,

p. 1021–1030.

McCulloch, M.T., and Gamble, J.A., 1991, Geochemical and geodynamical constraints on

subduction zone magmatism: Earth and Planetary Science Letters, v. 102, p. 35–374.

McDonough, W.F., 1990, Constraints on the composition of the continental lithospheric

mantle: Earth and Planetary Science Letters, v. 102, p. 358–374.

Oner, Z., and Dilek, Y., 2007, Depositional and tectonic evolution of the late Cenozoic

Alasehir supradetachment basin, western Anatolia (Turkey): Geological Society of

America Abstracts with Programs, v. 39, no. 6, 228 p.

———, 2008, Late-stage extensional tectonics of the Menderes metamorphic core complex,

Western Anatolia (Turkey), as observed in its supradetachment basin: Geological

Society of America Abstracts with Programs, v. 40, no. 6, 155 p.

Ozer, S., Sozbilir, H., Ozkar, I., Toker, V., and Sari, B., 2001, Stratigraphy of Upper

Cretaceous – Palaeogene sequences in the southern and eastern Menderes Massif

(Western Turkey): International Journal of Earth Sciences, v. 89, p. 852–866.

Pe-Piper, G., and Piper, D.J.W., 2001, Late Cenozoic, post-collisional Aegean igneous rocks:

Nd, Pb and Sr isotopic constraints on petrogenetic and tectonic models: Geological

Magazine, v. 138, p. 653–668.

———, 2002, The igneous rocks of Greece, the anatomy of an orogen, Beitrage zur

Regionalen Geologie der Erde: Berlin–Stuttgart, Gebruder Borntraeger, 573 p.

———, 2006, Unique features of the Cenozoic igneous rocks of Greece, in Dilek, Y., and

Pavlides, S., eds., Postcollisional tectonics and magmatism in the Mediterranean region

and Asia: Geological Society of America Special Paper, v. 409, p. 259–282.

Pe-Piper, G., Piper, D.J.W., and Matarangas, D., 2002, Regional implications of

geochemistry and style of emplacement of Miocene I-type diorite and granite, Delos,

Cyclades, Greece: Lithos, v. 60, p. 47–66.

Pearce, J.A., 1984, Role of the sub-continental lithosphere in magma genesis at active

continental margins, in Hawkesworth, C.J., and Norry, M.J., eds., Continental basalts

and mantle xenoliths, Shiva Geology Series: Nantwich, Shiva Publishing Limited,

p. 230–249.

Pearce, J.A., and Peate, D.W., 1995, Tectonic implications of the composition of volcanic arc

magmas: Annual Review of Earth and Planetary Sciences, v. 23, p. 113–134.

Pearce, J.A., Bender, J.F., Delong, S.E., Kidd, W.S.F., Low, P.J., Guner, Y., Saroglu, F.,

Yilmaz, Y., Moorbath, S., and Mitchell, J.J., 1990, Genesis of collision volcanism in

eastern Anatolia, Turkey: Journal of Volcanology and Geothermal Research, v. 44,

p. 189–229.

Reignier, J.-L., Mezger, J.E., and Passchier, C.W., 2007, Metamorphism of Precambrian-

Paleozoic schists of the Menderes core series and contact relationships with Proterozoic

orthogneisses of the western Cine Massif, Anatolide belt, Western Turkey: Geological

Magazine, v. 144, p. 67–104.

Rickwood, P.C., 1989, Boundary lines within petrologic diagrams which use oxides of major

and minor elements: Lithos: 22, p. 247–264.

Rimmele, G., Oberhansli, R., Goffe, B., Jolivet, L., Candan, O., and Cetinkaplan, M., 2003,

First evidence of high-pressure metamorphism in the ‘Cover Series’ of the Southern

Menderes Massif. Tectonic and metamorphic implications for the evolution of SW

Turkey: Lithos, v. 71, p. 19–46.

Ring, U., and Collins, A.S., 2005, U–Pb SIMS dating of synkinematic granites: timing of

core-complex formation in the northern Anatolide belt of western Turkey: Journal of

the Geological Society of London, v. 162, p. 289–298.

Ring, U., Willner, A.P., and Lackman, W., 2001, Stacking of nappes with different pressure–

temperature paths: An example from the Menderes nappes of western Turkey:

American Journal of Science, v. 301, p. 912–944.

32 Z. Oner et al.


Satir, M., and Friedrichsen, H., 1986, The origin and evolution of the Menderes Massif, W.

Turkey: A rubidium/strontium and oxygen isotope study: International Journal of


Seyitoglu, G., Anderson, D., Nowell, G., and Scott, B., 1997, The evolution from Miocene

potassic to Quaternary sodic magmatism in western Turkey: Implications for

enrichment processes in the lithospheric mantle: Journal of Volcanology and

Geothermal Research, v. 76, p. 127–147.

Shand, S.J., 1927, Eruptive Rocks: New York, John Wiley, 444 p.

Simpson, C., and Schmidt, S.M., 1984, An evaluation of criteria to deduce the sense of

movement in sheared rocks: Bulletin of Geological Society America, v. 94, p. 181–1288.

Simpson, C., and Wintsch, R.P., 1989, Evidence for deformation-induced K-feldspar

replacement by myrmekite: Journal of Metamorphic Geology, v. 7, p. 261–275.

Streckeisen, A., 1979, Classification and nomenclature of volcanic rocks; lamprophyres,

carbonatites and melilitic rocks: recommendations and suggestions of the IUGS

subcommission of the systematics of igneous rocks: Geology, v. 7, p. 331–335.

Sun, S.-S., and McDonough, W.F., 1989, Chemical and isotopic systematics of oceanic

basalts: implications for mantle composition and processed, in Saunders, A.D., and

Norry, M.J., eds., Magmatism in the ocean basins: Geological Society of London

Special Publications, v. 42, p. 313–345.

Thirlwall, M.F., Smith, T.E., Graham, A.M., Theodorou, N., Hollings, P., Davidson, J.P.,

and Arculus, R.D., 1994, High field strength element anomalies in arc lavas: Source or

processes: Journal of Petrology, v. 35, p. 819–838.

Thomson, S.N., and Ring, U., 2006, Thermochronologic evaluation of postcollision extension

in the Anatolide orogen, western Turkey, Tectonics, v. 25, TC3005, doi: 10.1029/

2005TC001833.

Thorpe, R.S., Francis, P.W., Hammill, M., and Baker, M.C.W., 1982, The Andes, in Thorpe

R, S., ed., Andesites: New York, John Wiley and Sons, p. 187–205.

White, S.H., 1976, The effects of strain on the microstructures, fabrics, and deformation

mechanisms in quartzites, Philosopical Transactions Society, London, Series A283,

p. 69–86.

White, A.J.R., and Chappell, B.W., 1977, Ultrametamorphism and granitoid genesis:

Tectonophysics, v. 43, p. 7–22.

Wilson, M., 1989, Igneous petrogenesis: A global tectonic approach: London, International

Thompson, 466 p.

Yilmaz, Y., 2002, Tectonic evolution of western Anatolian extensional province during the

neogene and quaternary: Geological Society of America Abstracts with Programs, v. 34,

no. 6, 179 p.

Yilmaz, Y., and Polat, A., 1998, Geology and evolution of the Thrace volcanism, Turkey:

Acta Vulcanologica, v. 10, p. 293–303.

Yilmaz, Y., Genc, S.C., Gurer, O.F., Bozcu, M., Yilmaz, K., Karacik, Z., Altunkaynak, S.,

and Elmas, A., 2000, When did the western Anatolian grabens begin to develop? in

Bozkurt, E., Winchester, J.A., and Piper, J.A.D., eds., Tectonics and magmatism in

Turkey and the surrounding area: Geological Society of London, Special Publications,

v. 173, p. 353–384.

Yilmaz, Y., Genc, S.C., Karacik, Z., and Altunkaynak, S., 2001, Two contrasting magmatic

associations of NW Anatolia and their tectonic significance: Journal of Geodynamics,

v. 31, p. 243–271.



PLEASE SCROLL DOWN FOR ARTICLE - Miami University · and dynamic recrystallization were most common...

Documents

Transcript of PLEASE SCROLL DOWN FOR ARTICLE - Miami University · and dynamic recrystallization were most common...