Abstract WD9

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Centennial memorial event of Graduate School of Science andFaculty of Science, Tohoku University

9 th INTERNATIONAL WORKSHOP ON

WATER DYNAMICS

DEEP CARBON CYCLE/BEYOND BRITTLE

March 7-9, 2012

Sendai International Center in Sendai, Japan

Sponsor

Tohoku University Global-COE Program

Global Education and Research Center for Earth and Planetary Dynamics


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We had the Great East Japan Earthquake and severe tsumani disasteron March 11 2011, and then we had spent unusual life after theearthquake. Tohoku University, the largest university in TohokuDistrict, was partly damaged by the earthquake; however, we cancontinue to perform high level research activities as well as previousconditions.

We also notice and conform the importance of Earth Science forhuman beings. Global COE (Center Of Excellence) project organizes

9th international workshop on WATER DYNAMICS around firstyear anniversary of the earthquake.

The Workshop will review the fundamental properties and reactivityof WATER, which means not only pure water but alsomulticomponent geofluids, and the workshop involves the role ofcarbon in the Earths interior for dynamics and evolution of the

Earth System.After the Fukushim Nuclear Power Disaster has drastically changedthe energy policy of the Japanese government. The government,industry, and citizens are much more positive to develop stable, safe,locally-distributed, and clean energy resources. Renewable energysuch as solar, wind and geothermal have been focused, andgeothermal has been considered as one of the most promisingsolutions for currently occurring energy-related crisis in Japan.


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= Tachibana Conference Hall, Sendai International Center =

Wednesday, March 7th, 2012Time Speaker Title Chairman

10:00-10:10 Eiji Ohtani Opening Remarks N. Tsuchiya

10:10-10:40 Greg Bignall Scientific Rationale and Economic Benefits for Deep (5 km) GeothermalDrilling in the Taupo Volcanic Zone, New Zealand

10:40-11:20 Gudmundur Omar Iceland Deep Drilling Project IDDP-1 in Krafla drilled into >900C hotmagma presently the worlds hottest production well (450C). Planning fordrilling well IDDP-2 at Reykjanes

11:20-12:00 poster presentation (2min introduction)

12:00-13:00 Poster Session

13:00-14:00 Lunch

14:00-14:40 Alexey Kiryukhin Possible Scientific Drilling Targets in Kamchatka, Russia A. Okamoto

14:40-15:20 Hirofumi MuraokaJapan Beyond-Brittle Project proposed for a geothermal energy paradigmshift in northeastern Japan

15:20-15:50 Hiroshi AsanumaSeismicity from geothermal reservoirs prospects of seismicity from

engineered geothermal systems in ductile zone15:50-16:00 Break

16:00-17:00 ICDP Project Discussion N. Tsuchiya

17:45 Workshop Banquet

Thursday, March 8th, 2012Time Speaker Title Chairman

09:30-10:00 Yangting LinH isotope constraints on the magmatic and meteoric water of Mars:Evidence from the GRV 020090 martian meteorite

Konstantine Litasov

10:00-10:40 Katsuyoshi Michibayashi Tonga Trench: A window to explore a mantle wedge system

10:40-10:50 Break

10:50-11:30 Shun-ichiro K arato Water in the deep interior of the Moon: geophysical constraints and itsorigin

11:30-12:10 Craig E. ManningpH buffering of subduction-zone fluids: implications for Earths deep carboncycle

12:10-13:00 Lunch

13:00-13:30 Poster Session

13:30-14:00 Konstantine Litasov Solidi and melting phase relations of alkaline carbonatite at the deep mantleconditions

Takeshi Sakai

14:00-14:30 Anton ShatskiyFormation and extraction mechanism of primary kimberlite melt:experimental constrains.

14:30-14:40 Break14:40-15:10 Seiichi Takami Experimental challenge to realize K4 crystals

15:10-15:50 Hiroaki OhfujiExperimental study on the phase transition mechanism of graphite todiamond under high pressure and high temperature Anton Shatskiy

15:50-16:00 Break16:00-16:30 Takeshi Sakai The effect of light elements on Earth's core properties16:30-17 :1 0 O liver T. Lord The Earths c ore: the deep est carbon reser voi r and other stori es

Friday, 9th March, 2012Time Speaker Title Chairman

10:00-10:30 Noriyoshi Tsuchiya Hydrot hermal Derived Fracturing: Natur al and Experimental Evidenc es A. Okamoto10:40 -11:20 Craig E. Manning Element mob il it y in lower c rustal and upper man tl e aqueous f lu ids

11:20-12:00 Derek ElsworthRoles of Fluid Pressure, Thermal and Chemical Effects in ConditioningPermeability and Triggered Seismicity in Enhanced Geothermal Systems

Lab Tour in Aobayama


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+#,-# Sendai International Center


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Oral Presentations

Scientific Rationale and Economic Benefits for Deep (5 km) Geothermal .....p.08

Iceland Deep Drilling Project IDDP-1 in Krafla drilled into >900C hot magma presently the worlds hottest production well (450C). Planning for drilling wellIDDP-2 at Reykjanes !!!!!!!!!!!!!!!!!!!!!!! ...p.09

Possible Scientific Drilling Targets in Kamchatka, Russia !!!!!!!! .p.10

Japan Beyond-Brittle Project proposed for a geothermal energy paradigm shiftin northeastern Japan !!!!!!!!!!!!!!!!!!!!!! ..! p.11

Seismicity from geothermal reservoirs prospects of seismicity from engineered

geothermal systems in ductile zone!!!!!!!!!!!!!!!!

..!

p.12

H isotope constraints on the magmatic and meteoric water of Mars: Evidencefrom the GRV 020090 martian meteorite !!!!!!!!!!!!!!! ..p.13

Tonga Trench: A window to explore a mantle wedge system !!!!!! ...p.14

Water in the deep interior of the Moon: geophysical constraints and its origin!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! .!! p.15


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pH buffering of subduction-zone fluids: implications for Earths deep carboncycle !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! p.18

Solidi and melting phase relations of alkaline carbonatite at the deep mantleconditions !!!!!!!!!!!!!!!!!!!!!!!!!!! ... ! p.19

Formation and extraction mechanism of primary kimberlite melt: experimentalconstrains !!!!!!!!!!!!!!!!!!!!!!!!!!!! ..p.20

Experimental challenge to realize K4 crystals !!!!!!!!!!!!! .p.21

Experimental study on the phase transition mechanism of graphite to diamondunder high pressure and high temperature !!!!!!!!!!!!! .! .p.22

The effect of light elements on Earth's core properties !!!!!!!! .! .p.23

The Earths core: the deepest carbon reservoir and other stories !!!! ...p.24

Hydrothermal Derived Fracturing: Natural and Experimental Evidences !! p.25

Element mobility in lower crustal and upper mantle aqueous fluids !!! ....p.26

Roles of Fluid Pressure, Thermal and Chemical Effects in ConditioningPermeability and Triggered Seismicity in Enhanced Geothermal Systems ! p.27


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Poster Presentations

(P1) Thermal Decomposition of Polycyclic Aromatic Hydrocarbons at 800-1100

K and 6-9 GPa: Implication to Earth and Planetary Carbon Dynamics ! ... ! p.28

(P2) Experimental Investigation of the Effect of Water on Fabric Development of

Anorthite !!!!!!!!!!!!!!!!!!!!!!!!!!! ..! ..p.29

(P3) Melting of Carbonated Peridotite at 10-20 GPa: Implication to SiO 2-

Saturation of Carbonated Magma in the Deep Mantle !!! ..! .! ..!!! .p.30

(P4) Experimental Study on Calcite Precipitation in Hydrothermal Condition

Modified after Geosphere Environment !!!!!!!!!!!! ... !!! .p.31

(P5) Enhanced Hydrogen Production via Sulfur Redox Cycle by Application of

Natural Hydrothermal Resource !!!!!!!!!!!!!!!!!!! .p.32

(P6) Sound Velocity Measurements in FeH using Inelastic X-ray Scattering:

Implications for Hydrogen Abundance in the Earths Core !!!!!! ... ! .p.33

(P7) Thermal Evolution in Malabar Area, Northern Part of the Wayang Windu

Geothermal Field: Evidence from Petrographic and Fluid Inclusion Studies ..p.34

(P8) Changes in Permeability and Flow Paths in a Carbonate Fracture duringDissolution Process under Confining Stress !!!!!!!!!!!!!! p.35

(P9) Melting relation of Fe 3C by in-situ X-ray Diffraction Experiments .... !! p.36


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Scientific Rationale and Economic Benefits for Deep (5Km) Geothermal

Drilling in the Taupo Volcanic Zone, New Zealand

Greg Bignall

Institute of Geological and Nuclear Science Ltd., Wairakei Research Center, New Zealand

E-mail address: [email protected]

The Taupo Volcanic Zone (New Zealand) is an active continental volcanic/back arc and fault-

controlled extensional basin, produced by westward subduction of the Pacific Plate beneath the

Australian-Indian Plate. The TVZ is a vast natural heat engine, and hosts several geothermal systems

that are developed for electric power generation. New Zealands geothermal resources are utilised to ~3

km and temperatures to ~340C. Current geothermal generation is ~760 MWe (~13% of New

Zealands total electricity generation). The theoretical deep (>4 km depth) energy potential in the TVZ

is massive, but are the resources realizable, and a realistic part of New Zealands energy future? Since

2009, New Zealand Government-funded research has examined the nature of deep geothermal activity

in the TVZ. Planning is underway for an ambitious and technically challenging project to drill, sample

(fluid and host rock) and assess the permeability structure of deep-seated TVZ geothermal activity.Drilling is aligned with international research objectives involving International Continental Science

Drilling Program (ICDP) and International Partnership for Geothermal Technology (IPGT)

relationships. The New Zealand geothermal industry is motivated to maximise the potential of their

resources, and their involvement in the TVZ science drilling project is essential. Scientific and

engineering know-how obtained will help overcome barriers that restrict deep geothermal resource

utilisation, whilst providing previously unobtainable insights into the structure and evolution of the

TVZ.


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Iceland Deep Drilling Project IDDP-1 in Krafla drilled into >900 hot

magma presently the worlds hottest production well (450 ). Planning

for drilling well IDDP-2 at Reykianes

Gudmundur Omar Fridleifsson 1, Wilfred A. Elders 2 and Bjarni Palsson 3

1. HS Orka hf, Brekkustigur36, Reykianesb r, Iceland

2. Dept. of Earth Science, University of California, Riverside, CA 92521 USA.

3. Landsvirkjun, Haaleitisbraut 68, IS 103, Reykjavik, Iceland


The Iceland Deep Drilling Project (IDDP) is investigating the economic feasibility of producing

electricity from supercritical geothermal reservoirs. Modelling suggests that producing superheated

steam from a supercritical reservoir could potentially increase power output of geothermal wells by an

order of magnitude. To test this concept the consortium intends to drill 4-5 km deep wells in three

different hightemperature geothermal fields in Iceland, Krafla, Hengill and Reykjanes. The drilling of

the IDDP-1 took place in 2009, but had to be terminated at 2.1 km depth when drilling into >900C hot

rhyolitic magma. Today the well is highly productive, estimated to be capable of generating 25-35

MWe from dry superheated steam produced from a contact zone above the magma intrusion. With the

current wellhead flowing temperature of 450C and enthalpy around 3200 kJ/kg, it can be claimed to

be the hottest producing geothermal well in the world. While flow testing to optimize utilization

continues, plans are underway to drill a 4-5 km deep well at Reykjanes in 2013-2014. If the IDDP

concept proves to be successful, such very high enthalpy geothermal systems may become significantresources worldwide in the future. International Science Workshop for IDDP-2 is being planned for

September 2012.


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Possible Scientific Drilling Targets in Kamchatka, Russia

Alexey V. Kiryuhin

Institute of Volcanology & Seismology FEB RAS, Piip 9, Petropavlovsk-Kamchatsky, Russia 683006


Mutnovsky magma-hydrothermal system connection.

At Mutnovsky (located 75 km to the south of Petropavlovsk Kamchatsky) there are two strong

arguments for a direct connection between geothermal production and active magma beneath the

volcano. First, the main production zone in the Mutnovsky field is a plane of high permeability that if

projected towards the volcano intersects the active conduit at shallow depth. Second, there is a

component of the producing fluid, defined in terms of O and H isotopic composition, for which the

only known equivalent is the Crater Glacier. The glacier apparently acts as the main source of meteoric

water recharge area for the fluids producing by exploitation wells. Exploitation of power plants started

in 2000-2002 years with total installed capacity of 62 MWe provides new information on geothermal

reservoir formation conditions and connections with adjacent thermal features.

Avachinsky-Koryaksky volcanic basin.

Both volcanoes are located 25-30 km to the north of Petropavlovsk Kamchatsky. High

temperature fluid reservoir adjacent to the north-north-east flank of Koryaksky volcano is revealed by

seismic activity distributions, fumaroles and thermal springs locations. The accessible drilling area was

estimated as more than 3 km 2. Geothermometers (Na-K) applied to thermal springs indicate

temperatures above 260 oC. Koryaksky volcano phreatic eruption 2008-2009 seems to be recharged

from this reservoir. Another fluid reservoir was penetrated at the south-eastern foothills of Avachinsky

volcano, this reservoir reveals significant gas discharge (CH 4).

The earthquakes precursors in wells and springs have been documented in both areas over the

past 30 years of observations.


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Japan Beyond-Brittle Project Proposed for a Geothermal Energy

Paradigm Shift in Northeastern Japan

Hirofumi Muraoka 1, Hiroshi Asanuma 2 and Hisao Ito 3

1. North Japan Research Institute for Sustainable Energy, Hirosaki University

2. Graduate School of Environmental Studies, Tohoku University

3. Center for Deep Earth Exploration, Japan Agency for Marine-Earth Science and Technology


For an energy paradigm shift in northeastern Japan after the tsunami disasters at March 2011,

geothermal energy is one of the most prospective candidates because northeastern Japan is blessed with

abundant geothermal resources. However, conventional geothermal power generation is not necessarily

enough to supply large amounts of electricity. The next generation geothermal power is an engineered

geothermal system (EGS). EGS power generation methods have two types bottle necks for practical

utilization; one is that the recoverability of injected water is about 50 % or less than that in fracture-

dominant regions like Japan inevitably requiring replenishment of voluminous injected water

throughout the power generation operation, and the other is that the injected water raises pore fluid

pressures of crustal rocks causing induced felt earthquakes. We propose a new type power generation

method using EGS that the two types bottle necks can be solved at the same time by the nucleation of

an artificial brittle fracture reservoir system completely surrounded in the ductile zones at a temperature

around 500 C which are already confirmed such as in the Kakkonda geothermal field, northeastern

Japan. This method would dramatically expand the exploitable geothermal resources to the thermal

conduction type resources beyond the brittle zones.


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Seismicity from Geothermal Reservoirs Prospects of Seismicity from

Engineered Geothermal Systems in Ductile Zone

Hiroshi Asanuma 1, Yusuke Mukuhira 1, and Hirofumi Muraoka 2


2. NJRISE, Hirosaki University


Seismic events from many of hydrothermal reservoirs and most of the engineered geothermalsystems (EGS) reservoirs have been used as one of the few methods which enables us to monitor

reservoir characteristics, including reservoir extension, distribution of flow paths, and dynamic

response to human operation to the reservoirs. Meanwhile, occurrence of seismic events with

unexpectedly large magnitude has been focused as one of the most serious negative impacts of the

geothermal development. Common risk of large induced seismicity has been pointed out in EOR in oil

industry, CCS, gas storage, and injection of wasted water.

Large seismic events collected at hydrothermal and EGS sites showed unique characteristics in

critical pore pressure for shear slip, spatio-temporal distribution of their hypocenters, stress drop, and

FPSs suggesting that the mechanism can not be simply modeled by asperity model which has been

commonly used in global seismology. We consider that development of EGS reservoirs in the ductile

zone have potential to avoid occurrence of large magnitude of induced seismicity because of expected

relatively homogeneous stress state in the ductile zone and isolated brittle zone in the ductile rock mass,

although basic studies should be made to scientifically discuss on seismicity from ductile EGS

reservoirs.


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Isotope Constraints on the Magmatic and Meteoric Water of Mars:

Evidence from the GRV 020090 Martian Meteorite

Yangting Lin, Sen Hu, Jianchao Zhang, Jialong Hao, Lu Feng, Wei Yang, Xuchao Zhao

Institute of Geology and Geophysics, Chinese Academy of Sciences


GRV 020090 is a lherzolitic shergottite probably derived from the enriched Martian mantle

and/or contaminated by the oxidized and enriched crust as the magma intruding into the subsurface ofMars. D/H ratios and water contents of silicate glass of melt inclusions in olivine and pyroxene

oikocrysts and apatite in the interstitial part were measured with CAMECA nanoSIMS 50L. Our

analyses show distinct correlation of the D/H ratios and water contents between the melt inclusions and

apatite. The negative relationship of the D/H and water content of apatite is consistent with previous

reports, which can be explained by crystallization of apatite from a melt contaminated by the crust that

contained meteoric water. The D/H ratios and water contents of the melt inclusions are positively

correlated, which was produced by H diffusion from the wall rock into the inclusions as the igneous

unit cooled down below the boiling temperature of water on Mars. This is a solid evidence for

temporary presence of liquid water on Mars, which was likely melted from H 2O ice in wall rock by the

intruded magma.


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Tonga Trench: A Window to Explore a Mantle Wedge System

Katsuyoshi Michibayashi, Shinkai Yuri

Institute of Geosciences, Shizuoka University


The Tonga trench is one of the deepest oceanic regions in the world (10,866 m). Various types

of rocks have been dredged and drilled at several localities on the landward slopes of the trench. In

particular, very pristine peridotites occur at the most deep landward trench slope. We show that the

trench can be divided into two regions: central region and northern region. The peridotites in the central

region have high-Cr# (0.46-0.83) which were typical of forearc peridotites, whereas the peridotites in

the northern region have evidences of the reaction with magma during partial melting. Moreover, they

remarkably reacted with melt and/or fluid. Olivine fabrics are characterized by E-type and D-type.

Although E-type and D-type are no clear relationship of mineral composition, grain size and

equilibrium temperature, the only difference between E-type and D-type were fabric intensities. This

difference suggests that pristine and serpentinized peridotites in the Tonga trench are deformed in the

region where high strain field occurred due to the dragged flow. Eventually, they expose in a very neatcondition (i.e. active tectonic erosion and fast ascent rate) resulting from an unique tectonic setting

including fast subducting plate (24 cm/yr), fast spreading plate (15 cm/yr) and slab rollback.


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Water in the Deep Interior of the Moon: Geophysical Constraints and Its

Origin

Shun-ichiro Karato

Yale University, Department of Geology and Geophysics, New Haven, USA


The recent measurements of some of the Apollo samples showed that some of the lunar samples

have evidence for a substantial amount of water in the interior of the Moon (e.g., [ Hauri et al. , 2011]).This is surprising because a commonly accepted compositional model of the Moon is highly depleted

in volatile elements (based on the compositions of many basaltic samples). Such a model is generally

considered to be consistent with a giant impact model for the origin of the Moon where extremely high

temperature after the impact likely removed a majority of volatile elements. However, the

interpretation of petrological observations is non-unique because of the large uncertainties in the

processes by which these samples might have been transported to the surface of the Moon.

Consequently, the wet deep mantle model of the Moon is still controversial.

In this presentation, I will provide additional evidence for the wet deep mantle of the Moon

from the analyses of geophysical observations (electrical conductivity and tidal energy dissipation).

The high-quality (better than Earth) model of electrical conductivity-depth profile is available for the

Moon due to the lack of the surface oceans. The conductivity in the deep mantle reaches ~0.1 S/m that

would require unacceptably high temperatures (T > 2000 K) if dry conditions and the low oxygen

fugacity are assumed. However, such conductivity values can be explained by modest temperatures if a

substantial amount of water is assumed. The tidal Q of the Moon is also surprisingly small (high energy

dissipation) although the Q in the shallow mantle (and the crust) of the Moon is very high. The tidal Qis mostly determined by the rheological properties of the deep mantle, and consequently, this

observation also suggests that the deep mantle of the moon is soft, that is consistent with wet deep

mantle model of the Moon.


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Why does the (deep) mantle of the Moon have such high water content if the Moon was formed by

giant impact? [ Elkins-Tanton and Grove , 2011] developed a model to explain some of the recent

observations of wet samples through the modeling of crystallization of the initially wet magma

ocean. Although such a model provides some insights into the depth variation of water content, this

model does not explain why the initial materials of the Moon were wet if the Moon was formed by agiant impact. I propose that a key to this puzzle is the fact that condensation after the giant impact

likely occurred in the high-pressure environment compared to the condensation in the solar nebula. The

pressure of the Moon forming nebula can be calculated from the mass and the size of the nebular

materials, and turns out to be on the order of 1-10 MPa at the distance close to the Roche limit where

much of accretion occurred [ Kokubo et al. , 2000]. Such a pressure is much higher than the pressure in

the representative region of the solar nebula (~10 -5 MPa (~10 Pa)). At this level of high pressure,

condensation from the gas should occur as gas ! liquid ( ! solid) as opposed to gas ! solid that

should occur in the high-vacuum environment [ Mysen and Kushiro , 1988]. Consequently, if the cooling

time scale of the nebula is longer than the time scale of accretion, then the Moon will be formed by the

accretion of liquids that have much higher water solubility than solid minerals. Currently available

modeling results suggest that such a condition is feasible although the uncertainties in the accretion

time scale are large. According to this model, the high water content in the deep Moon is essentially

due to the Moon formation from the dense proto-lunar nebula in which liquids phase are accumulated

to form the Moon rather than the solid particles. After the formation of the Moon, solidification and

chemical differentiation likely occurred and the stratification in water content resulted as shown by[ Elkins-Tanton and Grove , 2011]. Consequently, the shallow part of the Moon is relatively depleted

with water but the deep part contains a substantial amount of water. However, due to the extremely

high temperature in the proto-lunar nebula, dissociation of water into hydrogen + oxygen likely

occurred that resulted in the hydrodynamic loss of hydrogen leading to the increase in D/H ratio, a

result consistent with the isotopic observations [ Greenwood et al. , 2011].

Elkins-Tanton, L., and T. L. Grove (2011), Water (hydrogen) in the lunar mantle: Results from

petrology and magma ocean modeling, Earth and Planetary Science Letters , 307 , 173-179.

Greenwood, J. P., S. Itoh, N. Sakamoto, P. Warren, L. A. Taylor, and H. Yurimoto (2011), Hydrogen

isotope ratios in lunar rocks indicate delivery of cometary water to the Moon, Nature Geoscience , 4,

79-82.


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Hauri, E. H., T. Weinreich, A. E. Saal, M. C. Rutherford, and J. A. Van Orman (2011), High pre-

eruptive water contents preserved in lunar melt inclusions, Science , 333 , 213-215.

Kokubo, E., S. Ida, and J. Makino (2000), Evolution of a circumterrestrial disk and formation of a

single Moon, Icarus , 148 , 419-436.

Mysen, B. O., and I. Kushiro (1988), Condensation, evaporation, melting, and crystallization in the primitive solar nebula: Experimental data in the system MgO-SiO 2-H2 to 10 -9 bar and 1870 0C with

variable oxygen fugacity, American Mineralogist , 73, 1-19.


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pH Buffering of Subduction-Zone Fluids: Implications for Earths Deep

Carbon Cycle

Craig E. Manning

University of California, Los Angeles, CA, 90095, USA


Volcanic arcs return CO 2 to the Earths surface, but the transfer mechanism is problematic. Phase

equilibrium studies of subduction zones indicate that, in the absence of fluids, carbonate minerals are

quite stable along slab P-T paths, so their simple breakdown cannot be a significant mechanism by

which CO 2 is transferred, at least to subarc depths. Alternatively, CO 2 can be stripped from slab

carbonates by infiltration of H 2O-rich fluid, driving reactions that can be modeled by aragonite + quartz

= wollastonite + CO 2. However, the high P and low T of subduction zones such as Cascadia, western

North America, causes maximum fluid CO 2 concentrations to remain low at depths


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Solidi and Melting Phase Relations of Alkaline Carbonatite at the Deep Mantle

Conditions

Litasov K.D., Shatskiy A., Ohtani E.

Department Earth Planetary Materials Science, Tohoku University


Studies of melting relations in carbonate peridotite and eclogite often fail to determine true

solidus due to low-temperature stability of poorly resolvable small fractions of alkali-bearingcarbonatite melt or solid phases. In this report we determined solidi and phase relations in model K-

and Na-bearing carbonatite systems and discuss stability of alkali carbonates and their effect for mantle

melting and carbon transport. Two starting materials of Ca-Mg carbonatite melt enriched in Na 2O and

K 2O, respectively (2 and 7 wt% and vice versa), were examined. Minor SiO 2 and FeO were also added.

Experiments were conducted using multianvil technique at 3-21 GPa and 750-1400 oC. The solidus

temperature of Na- and K-carbonatite is located near 750 oC at 3 GPa and 850 oC at 6 GPa. Significant

increase of the solidus temperature up to 1150 oC was found between 6 and 10 GPa. Then, between 10

and 21 GPa the solidi are flat. In the Na-bearing system 6-10 wt% Na 2O can be dissolved in aragonite,

which is nearly all Na 2O added to the system. Several stable alkali-bearing carbonates were observed in

the both K-bearing and Na-bearing systems. Most important of them are (K,Na) 2Mg(CO 3)2 and

(K,Na) 2Ca4(CO 3)5. The K 2O content in these carbonates is always dominates over Na 2O even in the

Na-bearing system. Silicate phases include diopside at pressures below 15 GPa, Ca-Fe-bearing melilite-

like phase at 15 GPa, and Ca-perovskite and stishovite at 21 GPa. Low-degree partial melts are Na- and

K-rich for Na- and K-bearing carbonatite, respectively, due to early melting of alkali carbonatite.

Magnesite is the liquidus carbonate phase along with silicate at all pressures. Comparison of solidi for

Na- and K- bearing carbonatite with subduction geotherms indicate stability of alkali carbonates along

cold subduction paths. Melting of subducting alkaline carbonates would likely occur at the transition

zone depths to produce mobile carbonatite melt diapirs, migrating upwards, modifying and oxidizing

the upper mantle and initiating volcanism at the surface.


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Formation and Diapiric Mobilization of Primary Kimberlite Melts: Experimental

Constrains

Shatskiy A., Sharygin I.S., Litasov K.D., Ohtani E.

Department Earth Planetary Materials Science, Tohoku University


Kimberlites are the deepest probe into Earths mantle (>150-250 km). However, our

understanding of kimberlite ascent is hampered by uncertainty about the compositions of primary

kimberlite melts. It is generally considered that kimberlite rocks represent the ultramafic nature of the

parental melt composition. Numerous findings of water depleted alkali-Ca-carbonatite melt inclusions

enriched in Fe, Ti, Cl, P, and S in olivine and ilmenite from kimberlites and xenogenic nature of ! 40

vol.% of olivine in a groundmass from kimberlites worldwide make questionable ultramafic

paradigm. To clarify this problem we performed experiments on melting phase relations in an

exceptionally fresh kimberlite group I from Udachnaya-East kimberlite (UEK) pipe at 3.0-6.5 GPa and

900-1500C. Observed crystallization sequence at 6 GPa includes Al-spinel, olivine, perovskite, Ca-

rich garnet, aragonite, and apatite. The system did not achieve complete melting even at 1500C and

6.5 GPa. Based on the partial melt composition we suggest that during its ascent via the lithospheric

mantle UEK was a mixture of carbonatite melt and xenoliths. Primary group I kimberlitic magma was

Na-K-Ca-carbonatite containing


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Experimental Challenge to Realize K4 Crystal

Seiichi Takami

Institute of Multidisciplinary Research for Advanced Materials, Tohoku University


Recently, Sunada proposed three dimensional K4 crystal structure that comprises all-equivalent

sp2 carbon atoms based on topological study. Inspired from this mathematic proposal, we studied the

properties of K4 crystals using computational chemistry. The results suggested that the K4 crystals

would be synthesized under high pressure with co-existing elements including Na, Mg etc. We also

proposed similar K4 structure of BN with co-existing elements. This presentation will focus on the

predicted properties of K4 crystals and its periphery. We will also show our efforts to synthesize K4

crystals


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Phase Transition Mechanism and Microstructure Evolution through

GraphiteDiamond Transition under High Pressure and High

Temperature

Hiroaki Ohfuji

Geodynamics Research Center, Ehime University, Japan


The phase transition mechanism of graphite-diamond transition was studied through the

microstructural observation of diamond samples synthesized by the direct conversion of graphite under

a wide range of PT conditions (15-50 GPa and ~1000-3000C). The results showed that the transition

mechanism and the resultant microstructure of diamond synthesized depend largely on the crystallinity

of initial graphite sources but less on PT conditions and local stress. When well-crystalline graphite is

used as a starting material, it transforms to diamond by a diffusion-less, martensitic process via

hexagonal-diamond as an intermediate phase. In this process, the original layered structure of graphite

is substantially maintained after phase transition, resulting in the formation of lamellar structure. On the

other hand, when started with poorly crystalline graphite, which involves a significant number of sp3-

like bonds at lattice defects and crystal surfaces, spontaneous nucleation of diamond occurs

preferentially at those active bonds. As the result, granular microstructure is produced by diffusion-

controlled nucleation and growth of nano-diamonds. This suggests that microstructure and the

corresponding physical properties of synthetic polycrystalline diamond can be controlled by carefully

choosing initial graphite sources based on their crystallinity.


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The Effect of Light Elements on Earth's Core Properties

Takeshi Sakai 1, Suguru Takahashi 1, Yuki Shibazaki 1, Seiji Kamada 2, Hidenori Terasaki 3, Eiji Ohtani 1

1. Department of Earth and Planetary Materials Science, Graduate school of Science, Tohoku

University

2. Department of Geology, University of Illinois

3. Department of Earth and Space Science, Osaka University


Since Earths core density is lower than that of pure iron, it should contain a few percent of

light elements such as carbon (C), hydrogen (H), sulfur (S), oxygen (O), and silicon (Si). The existence

of light element has large effects on the core material properties (density, melting temperature, sound

velocity, etc.). We investigated about the melting and phase relation for Fe-C, Fe-Si, Fe-O-S system,

and the equation of state of Fe-H, Fe-S and Fe-Si alloys, and also the sound velocity of FeH x. We

conducted the high pressure and temperature experiments using laser heated diamond anvil cell. The

melting, phase, and density of samples were determined by powder X-ray diffraction study at SPring-8

BL10XU. The sound velocity of FeH x was measured by the inelastic X-ray scattering experiment at

SPring-8 BL35XU. Our results show that the hexagonal close-packed structure is plausible for the

inner core in the cases of Fe-H, Fe-Si, and Fe-S system. The inner core boundary temperature is

estimated to be 5630 K for Fe-O-S system. We suggest three compositional models for the inner core

based on the equation of state (and the sound velocity of FeH x). Fe-5wt.%Ni-5.7wt.%S, Fe-5.4wt.%Ni-

5.8wt.%Si, and FeH 0.13 (0.23 wt.%H) can explain the inner core density.


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The Earths core: The Deepest Carbon Reservoir and Other Stories

Oliver T Lord 1, Michael J. Walter 2, Rajdeep Dasgupta 3, Dave Walker 4 and Simon M. Clark 5

1. Department of Earth Sciences, University College London, Gower Street, London, WC1E 6BT, UK

2. School of Earth Sciences, University of Bristol, Wills Memorial Building, Queens Road, Bristol,

BS81RJ, UK

3. Department of Earth Sciences, Rice University, 6100 Main Street, MS 126, Houston, Texas, USA

4. Lamont-Doherty Earth Observatory, P. O. Box 1000, 61 Route 9Q, Palisades, NY 10964-1000, USA

5. Department of Earth and Planetary Sciences, Macquarie University, Sydney, NSW2109, Australia


We have determined the Fe-C phase diagram up to 70 GPa using a range of techniques,

including synchrotron-based x-ray imaging of spatially resolved components within the laser-heated

diamond anvil cell. These investigations suggest that the carbon content of the eutectic drops rapidly

with pressure, becoming negligible by ~50 GPa and that at ~120 GPa, Fe 3C (cementite) will be

replaced at the solidus by Fe 7C3. Whether Fe 7C3 crystallises within the inner core, or whether the

carbon budget dissolves into the iron phase depends on the bulk core carbon content and the

composition of this new Fe+Fe 7C3 eutectic. I will also discuss some of the implications that these

results may have for the mantle, which is expected to contain both metallic iron and free carbon. These

results represent a tiny fraction of the numerous exciting advances which are currently being made

within the field of core science. These are being driven by rapid improvements in our capability to

reach extreme pressures and temperatures in the laboratory and to make an ever widening range of

useful measurements once we are there.


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Hydrothermal Derived Fracturing: Natural and Experimental Evidences

Noriyoshi Tsuchiya

Graduate School of Environmental Studies, Tohoku University


Veins are intimately related to fracture mechanics, since most veins form by crystal growth into

space generated by fractures. Here, problems are why and how host rocks can be failed in certain

conditions. We could observe hydrothermal brecciation in several geological settings, such asaccretionary prism, mineralized area, and metamorphic rocks. Hydrothermal breccias was formed by

explosive failure without any chemical reactions such as dissolution and precipitate. According to field

observation and lab work, we have to consider about meanings of "hydrothermal" and "brecciation",

and then their relation. We already proposed "HDF: Hydrothermally Derived Fracturing". Fluids has

great role to create fracture networks as an explosive failure. Recent progress in field observational,

experimental and theoretical research concerning "Hydrothermal Brecciation" and "Hydrothermally

Derived Fracturing" will be presented.


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Element Mobility in Lower Crustal and Upper Mantle Aqueous Fluids

Craig E. Manning

University of California, Los Angeles


Mineral solubility in pure H 2O is a poor guide to assessing minor-element transfer by high-

pressure fluids. This is because interactions with the major solutes derived from host lithologies control

on element mobility. This can be seen with three examples. First, solubility of Al is low in pure H2O;however, in the presence of SiO2 its solubility is dramatically higher. This arises from formation of

polymerized Al-Si clusters. Even higher solubilities result from addition of alkalis. In deep fluids, Al is

one of the most soluble elements in deep fluids. A second example is that low rutile solubility in pure

H2O at subduction zone conditions fails to explain occurrence of this phase in veins in high P rocks.

However, TiO 2 solubility is greatly enhanced dissolved Na-Al silicates, via incorporation in Na-Ti

complexes or Na-Al-Si oligomers. Experimentally constrained solubility data indicate that at 600 C

along model slab geotherms, rutile solubility in H 2O is 2 ppm Ti, whereas in H 2O equilibrated with

cpx+mica+quartz the high dissolved Na-Al-Si yield 88 ppm Ti. If albite-H 2O fluids are supercritical,

even greater Ti transport is possible. Finally, alkali halides are also important complexing agents. At

800C, 1 GPa, CePO 4 monazite and YPO 4 xenotime solubilities are very low in pure H 2O but are

significantly enhanced by NaCl via REE/Y-chloride and Na-phosphate complexing. This strongly

increases REE mobility. In general, the influence of aqueous complexing on element solubility

highlights that the role of fluids in element recycling can vary widely.


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Roles of Fluid Pressure, Thermal and Chemical Effects in Conditioning

Permeability and Triggered Seismicity in Enhanced Geothermal Systems

Ghazal Izadi 1, Baisheng Zheng 1, Joshua Taron 1,2, Derek Elsworth 1

1. Department of Energy and Mineral Engineering, EMS Energy Institute and G3 Center, Pennsylvania

State University, University Park, Pennsylvania, USA

2. Helmholtz Center for Environmental Research, Leipzig, Germany


The evolution of permeability, heat or diffusive transfer area and triggered seismicity are

intimately linked in forced-circulation systems such as EGS, CCS and unconventional hydrocarbon

reservoirs where conditions are pushed far-from-equilibrium. We explore this evolution subject to

coupled THMC processes in a prototypical EGS reservoir. We accommodate the influence of early-

time changes in effective stress, mid-time changes in thermal stresses and ultimately incorporate long-

term changes due to chemical effects. We develop a micromechanical model to represent the failure

process and apply this model to represent energy release from individual critically oriented fractures.The changing stress state is calculated from the pore pressure, thermal drawdown and chemical effects

for a coupled THMC model with dual porosity. This model is applied to a doublet geometry to explore

the spatial and temporal migration for permeability evolution, access to reactive surface area and the

triggering of seismicity as stimulation then production proceeds. Seismic activity is initially

concentrated around the near-wellbore injection region. It is earliest for closely spaced fractures in

reservoir rocks where the thermal drawdown of stress is largest at early times and results in numerous

low-magnitude events. These observations are used to define the evolution of spatial changes within

the reservoir and their migration with production, dependent on the mobilization of relic fractures.


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(P1) Thermal Decomposition of Polycyclic Aromatic Hydrocarbons at 800-1100 K

and 6-9 GPa: Implication to Earth and Planetary Carbon Dynamics

Chanyshev, A.D. 1, Litasov, K.D. 1,2 *, Shatskiy, A. 1,2 , Furukawa, Y. 2, Nemoto, M. 3, Mochizuki, S. 3,

Ohtani, E. 2, Funakoshi, K. 4

1. V.S. Sobolev Institute of Geology and Mineralogy, Novosibirsk, Russia

2. Department of Earth Planetary Materials Science, Tohoku University

3. Instrumental Analysis Group, Graduate School of Engineering, Tohoku University

4. SPring-8, Japan Synchrotron Radiation Research Institute, Kouto, Hyogo 678-5198, Japan


The origin of various deep-seated hydrocarbons was widely discussed in relation to the nature of

C-O-H fluid. Some theoretical calculations of equations of state for a range of hydrocarbons indicate

their possible increased stability in the deep mantle. These components, especially, polycyclic aromatic

hydrocarbons (PAHs), were found in natural samples inclusions in deep diamonds and garnets,

meteorites, as well as detected in the other planets and satellites and interstellar matters. To date we

have several important contributions from experimental petrology. Composition of C-O-H fluids under

controlling oxygen fugacity was measured in samples quenched after piston-cylinder and multianvil

experiments. They reveal CH 4- and H 2-bearing compositions with subordinate H 2O at 3-6 GPa and

1200-1600 oC. Direct observation of methane formation from carbonate and methane dissociation to

heavy alkanes was demonstrated in the diamond anvil cell experiments at 5-10. In present project we

studied temperature stability and decomposition products of a range of PAHs at pressures up to 20 GPa

using multianvil high-pressure apparatus and in situ X-ray diffraction at SPring-8. We successfully

observed X-ray diffraction patterns of PAHs at high pressure. Disappearance of diffraction lines of

PAHs was used as a detection of their decomposition. The decomposition of several PAH, ranging in

atomic mass from naphthalene to pyrene and coronene was observed at 550-650 oC and 6-9 GPa. We

observed strong polymerization of PAHs in the experiments at 500 oC and 7 GPa analyzed by MALDI


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and gas chromatography. Our data clearly show that PAHs cannot be stable at the average PT-

conditions of the upper mantle.

(P2) Experimental Investigation of the Effect of Water on Fabric

Development of Anorthite

Jun-ichi Fukuda, Jun Muto, Hiroyuki Nagahama

Department of Earth Sciences, Graduate School of Science, Tohoku University


We performed deformation experiments of polycrystalline anorthite using a pressure-medium

(Griggs-type) deformation apparatus under lower-middle crustal conditions. An100 polycrystal with

the average grain size of 3 # m was sintered as a starting material. Water was introduced into the sample

at high temperature (up to 950 C) and pressure (1.0 GPa), and the samples were deformed under

differential stress (up to 800 MPa) with the strain rate of up to 10 5/sec. After the experiments,

development of crystal preferred orientation (CPO) was inferred at 500 # m from the rim of the sample,

as concentration of interference color under a polarized optical microscope. In this region also, the

reaction of An100 + H 2O to zoisite was seen in an infrared spectrum as OH vibrational bands due to

zoisite around 3200 cm 1, and these bands were decreased from the rim. These observations indicate

that both plastic deformation and reaction occurred due to concentration gradient of water. We will

discuss changes in stress/strain due to concentration gradient of water in a polycrystalline anorthite

which is a load-bearing framework of the lower-middle crust.


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(P3) Melting of Carbonated Peridotite at 10-20 GPa: Implication to

SiO 2-Saturation of Carbonated Magma in the Deep Mantle

Ghosh S., Litasov K.D., Ohtani E.

Department of Earth Planetary Materials Science, Tohoku University


It is thought that kimberlite magma is originated from enriched deep mantle in the cratonic

roots or asthenosphere. Recent models suggest primary SiO 2-depleted or even carbonatitic

compositions for primary kimberlite magmas. Experimental studies of the systems, containing C-O-Hvolatiles, are critical for understanding the origin of kimberlite and carbonatite magma. In this work we

performed a series of multianvil experiments on two carbonate-bearing peridotite compositions (ACP:

alkali-rich carbonated peridotite + 5.0 wt% CO 2; and PERC: peridotite + 2.5 wt% CO 2) from 10 to 20

GPa and temperature from 1500 to 2100 oC to determine the phase relations and melt compositions of

carbonated peridotite in the upper mantle and transition zone in relation to generation of kimberlite-

and carbonatite-like magmas.

Near-solidus (ACP: 1400-1630 oC between 10 and 20 GPa) carbonatitic partial melts with 40 wt% CO 2 gradually change to carbonated silicate melts with >25 wt% SiO 2 and


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(P4) Experimental Study on Calcite Precipitation in Hydrothermal

Condition Modified after Geosphere Environment

Michimasa Musha, Noriyoshi Tsuchiya, Atsushi Okamoto

Graduate School of Environmental Studies


To reduce greenhouse gas (CO 2, CH 4 etc) in the atmosphere, the carbon storage underground

has been tried; however, it is considered to be difficult to precipitate calcite in reasonable timescale. In

contrast, calcite veins are very common in the oceanic crusts, metamorphic rocks, and accretionary

prisms. The purpose of this study is to understand the controlling factors on calcite precipitation under

conditions of calcite-vein formation (fluid compositions, P-T conditions, host rock types).

As a first step, we conducted hydrothermal flow-through experiments to precipitate calcite on

limestone substrates by using the temperature dependency of solubility. After the run of 240 h (10

days), observation of the surface morphologies of the substrates by SEM and thin sections by optical

microscope reveal that euhedral calcite crystals with size of 0.02-0.03 mm grew from the calcite in the

substrates.Second, we conducted flow-through experiments at 300 to precipitate calcite from natural

rock samples with NaHCO 3 solution (pH 8.4). After the run of 240 h, observation of the surface of the

substrates by SEM and EDS reveal that calcite crystals with size of 0.01 mm precipitated on the

substrates with clay minerals and apatite.

Our results suggest that calcite veins could be formed at high temperature around 300 C, in

alkaline fluids, if fluids saturated with calcite by Ca from host rocks and CO 32- in the crustal fluids.


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(P5) Enhanced Hydrogen Production via Sulfur Redox Cycle by

Application of Natural Hydrothermal Resource

Putri Setiani 1, Javier Vilcaez 2, Noriaki Watanabe 1, Atsushi Kishita 1, Noriyoshi Tsuchiya 1


2. Frontier Research Center for Energy and Resources (FRCER), School of Engineering, Tokyo

University


Hydrothermal condition is known to be beneficial as a reaction medium due to its effectiveness

and environmental benignity. This condition of high temperature water is naturally provided in the

earth interior, e.g. in geothermal system. On the other hand, hydrogen is known as an important

substance in industries and also a promising energy carrier. This study proposes a hydrogen production

method that could utilize the natural hydrothermal resources as an environmentally friendly heat source

for the reactions. In this method, hydrogen produced via sulfur redox-cycle which consists of two half

cycles: (1) hydrogen production from an aqueous alkaline solution at hydrothermal condition wheresulfide, HS - and S 2-, acts as reducing agent of water, and (2) sulfide regeneration at milder condition

with an organic compound, i.e. glucose acting as reducing agent of polysulfide and sulfur oxyanion

formed in the first half cycle. A hydrogen production through the sulfur redox cycle was also

demonstrated by following procedure: 1 st hydrogen production - sulfide regeneration - 2 nd hydrogen

production, where the hydrogen production and sulfide regeneration were conducted at 300 C and 105

C, respectively. As sulfide is regenerable, glucose is considered as the raw material. Results indicated

that hydrogen production from 1 mol glucose was greater than that by hydrothermal gasification at

much higher temperatures up to 500 C.


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(P6) Sound Velocity Measurements in FeH using Inelastic X-ray

Scattering: Implications for Hydrogen Abundance in the Earths Core

Yuki Shibazaki 1, Eiji Ohtani 1, Takeshi Sakai 1, Hiroshi Fukui 2, 3 , Seiji Kamada 1, Alfred Q.R. Baron 2,

4, Naoya Nishitani 1, Naohisa Hirao 4, Kenichi Takemura 5

1. Department of Earth and Planetary Material Sciences, Tohoku University

2. Materials Dynamics Laboratory, RIKEN SPring-8 Center

3. Graduate School of Material Science, University of Hyogo

4. Japan Synchrotron Radiation Research Institute (SPring-8/JASRI)

5. Advanced Materials Laboratory (AML), National Institute for Materials Science (NIMS)


The Earths interior has been directly investigated by seismic wave propagation and normal

mode oscillation. In particular, the distributions of density and sound velocity are available to study the

Earths core (e.g. PREM). The inner core, which is solid state, is approximately 3 % less dense than

pure iron, and it is considered that the core consists of iron and light elements. In this work, wedetermined the compressional sound velocity ( V p) of iron hydride (FeH) at high pressure using inelastic

X-ray scattering (IXS) in order to constrain the abundance of hydrogen in the Earths core by matching

the density and sound velocity of FeHx to those of PREM.

The IXS experiments and in situ X-ray diffraction (XRD) experiments were conducted up to 70

GPa and room temperature at BL35XU and BL10XU of the SPring-8 facility in Japan, respectively.

High-pressure conditions were generated using a symmetric diamond anvil cell (DAC) with tungsten

gaskets. We show that FeH follows Birchs law for V p above 37 GPa, namely a linear dependence

between velocity and density. The estimated V p, extrapolated to core conditions, is compared with

PREM. Our results provide that the Earths inner core could contain ~ 0.2 wt% hydrogen.


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(P8) Changes in Permeability and Flow Paths in a Carbonate Fracture

during Dissolution Process under Confining Stress

Imam Fathoni Rasyid, Takuya Ishibashi, Noriaki Watanabe, Noriyoshi Tsuchiya

Graduate School of Environmental Studies


A flow-through experiment with HCl aqueous solution (pH: approximately 3.4) was conducted

on fractured Ryukyu limestone (Okinawa, Japan), which contained either a single tensile or single saw-

cut fracture, under stress at the room temperature. The tensile fracture was used to mimic a natural

(variable-aperture) fracture. The saw-cut fracture was used for a comparison because a natural fracture

is sometimes assumed as such a non-variable aperture fracture. Experimental results showed different

rates of permeability increase between the tensile and saw-cut fractures, where the rate of permeability

increase in the tensile fracture was smaller than that in the saw-cut fracture. Results of a numerical

analysis of fracture flow, in which fracture surface topographies before and after the experiment were

used, showed that fluid flow occurred along preferential flow paths, and increased aperture pointsseemed to have a relation to the flow paths. Experimental and numerical results indicated that the rate

of permeability increase in a natural fracture is smaller than a prediction using a non-variable aperture

fracture, because dissolution of fracture surfaces occurred in smaller area of the fracture plane due to

the preferential flow paths.


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(P9) Melting relation of Fe 3C by in-situ X-ray Diffraction Experiments

Suguru Takahashi 1, Eiji Ohtani 1, Takeshi Sakai 1, Yuki Shibazaki 1, Naoya Nishitani 1, Itaru Ohira 1,

Takanori Sakairi 1, Naohisa Hirao 2, Yasuo Ohishi 2

1. Department of Earth and Planetary Materials Science, Graduate School of Science, Tohoku

University,

2. Japan Synchrotron Radiation Research Institute


The Earths core is regarded as an Fe-Ni alloy but the density of the core is lower than that of

pure Fe at pressures and temperatures corresponding to the core conditions. Therefore, the Earths core

is supposed to contain light elements and carbon is one of the candidates of the light elements to

explain the density deficit of the Earths core. Until now, many studies on physical and chemical

properties of Fe-carbides, such as Fe 3C and Fe 7C3, have been carried out at high pressure. Especially,

the recent studies on the melting of Fe 3C were reported by Nakajima et al. (2009) and Lord et al.

(2009). However, there are obvious discrepancies between the melting curves of Fe 3C in the previous

studies. In order to reveal the uncertainty of the melting temperature of Fe 3C and discuss the behaviors

of carbon in the Earths core, the melting temperatures of Fe 3C were determined based on in situ X-ray

diffraction experiments.

We determined the melting relation of Fe 3C up to 70 GPa. The melting temperature (both

solidus and liquidus) of Fe 3C is close to Nakajima et al. (2009) up to 30 GPa but becomes close to that

reported by Lord et al. (2009) at higher pressure conditions. The present experiments revealed that

Fe3C was stable as a subsolidus phase at least up to 70 GPa. This indicates that Fe 3C is a potential

candidate of the Earths inner core.

Abstract WD9

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