CL-spectral analysis of dolomite samples reveals that divalent Mn ions act as an activator for red CL emissions which can be divided into two components related to Ca and Mg sites occupied by Mn ions. Temperature-controlled CL measurements show a quenching effect on CL intensity form -200 to -100 degrees C, and sensitizing effect from -100 to -50 degrees C, but a quenching effect above 0  degrees C.

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Cathodoluminescence (CL) analysis of barytocalcite reveals a strong and broad emission at 600 nm in red region, which can be assigned to an impurity center of divalent Mn ion as an activator. The peak wavelength is lower than those of other calcite type carbonates, suggesting large M-O distance of this mineral. The CL intensity indicates a temperature quenching in the range from -190 to 25 degrees C.

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Epidote [Ca₂Al₂(Al,Fe)Si₃O₁₂OH] is a common rock forming mineral found low-grade metamorphic zones, develops complex zoning and wide-range of diversity in its chemical composition. The distribution of Fe²⁺ - Fe³⁺ ions in the crystal structure of the epidote is analyzed by the Möessbauer spectrometry and the order-disorder in the epidote can be calculated from the distribution. The M1 site distribution ratio is treated as the index of the formation temperature of the epidote. In this work, the M1/M3/M3' ratio of some epidote samples are determined and the formation temperature of the samples are estimated.

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When magnetite undergoes low temperature oxidation, vacant sites are formed at octahedral sites. So we can estimate a degree of low temperature oxidation by measuring vacant sites in crystal structure of magnetite. Natural magnetite has solid solution between Fe₃O₄ and Fe₂TiO₄.Ti⁴⁺ must be considered to estimate vacant site of titanomagnetite by Mössbauer spectra, because Ti⁴⁺ must be vacant for Mössbauer spectra. However, method of correction remains unsolved at Mössbauer spectroscopy. Therefore, we considered and examined a new correction method at Mössbauer spectroscopy.

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Direct observation of self-diffusion of hydrogen in ice Ih

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Vacancies are introduced into octahedral sites of titanomagnetite as titanomagnetite’s oxidation.The nonstoichiometry of titanomagnetite is expressed as degree of oxidation, or ratio of  vacancies against O₄. The degree of oxidation,or ratio of vacancies can be estimated by Mossbauer spectroscopy and X-ray diffraction. In this study, several nonstoichiometric natural magnetite were synthesized, and their degrees of oxidation were measured by  both methods.As a results, equations of degree of oxidation are suggested, and degree of oxidation measured by Mossbauer spectroscopy are consistent with those by X-ray diffraction.

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Shimazakiite is a new borate mineral occurs in skarn deposits at Fuka, Okayama Prefecture Japan. From single crystal X-ray diffraction studies of shimazakiite, two polytypic structures, shimazakiite-4M and shimazakiite-4O were found. Ideal chemical formula of shimazakiite is Ca₂B_2−xO_5−3x(OH)_3x (x = 0~0.06) and there is no distinct difference in chemical compositions of two polytypes. Shimazakiite-4M has a space group of P2₁/c with a = 3.5485(12), b = 6.352(2), c = 19.254(6) Å, and β = 92.393(13)º. Shimazakiite-4O has a space group of P2₁2₁2₁ with a = 3.55645(8), b = 6.35194(15), and c = 19.2534(5) Å.

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We have conducted the single crystal X-ray diffraction studies at low- and high-temperatures of NaSr₂Mg₂V₃O₁₂ and Na₃Sc₂V₃O₁₂ garnets, and have examined the reason for the difference in the atomic displacement behaviors of Z cations between both garnets. Consequently, it has been suggested that in the former garnet the V static disorder exists in [100], whereas in the latter garnet there is not the V static disorder.

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A lot of studies have been carried out  on cordierite by many geologists and mineralogists. One of the important characteristics of Cordierite is its low thermal expansivity and an anisotropy of thermal expansion coefficient. This characteristic thermal properties have been attracted not only mineralogists but ceramic scientists' attention. Krosaki Harima Corporation designed, "NEXCERA" as new ceramics achieved almost zero thermal expansivity and excellent mechanical characteristics. New data taken by TEM  and SEM will be shown in this session. And the XRD experiment shows chracteristic properties of cordierite. These expansion characters will be discussed with that of bulk volume variation. 

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In order to clarify the relationship between the structures and their unique properties, radial distribution function (RDF) analysis was carried out by the ordinary X-ray diffraction by using Mo Ka radiation. The features of obtained RDFs agree well with those of the diffraction patterns. The usefulness of the pair function method together with RDF simulation of related crystalline materials will be demonstrated. 

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Sibirskite and parasibirskite are in the relation of polymorphism, and occur at Fuka mine, Okayama Prefecture. To determine the formation condition of sibirskite and parasibirskite, they were synthesized from natural takedaite. Consequently, both of them were formed with 1000atm and 573K for 7 days, and only Sibirskite was formed with the same condition for 14 days. In addition, the mixtures of them were synthesized. Consequently, the upper limit of the stable temperature and pressure conditions of Sibirskite is estimated between 623K and 673K at 1500atm, and between 673K and 723K at 500atm. In the higher temperature, Sibirskite were changed into Shimazakiite.

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Si for Al substituted mayenite (C12A5S4) was obtained by thermal dehydration of hydrogrossular at 700°C. Hydration of Si-substituted mayenite was investigated using powder X-ray diffraction method and Raman spectroscopy. The cell parameter and the Raman peak that was related to hydroxide ion were increased over time. When the sample was reheated to a temperature of 1000 degrees, the Raman peak that was related to hydroxide ion disappeared.

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Synthetic experiments between hydrothermal solution - cordierite in the presence of K,Na,Ca in a Fe end-member neighborhood were performed. Either alkali element of Na,Ca,K existed in solution, cordierite was synthesized. However, the composition that was near to the Fe-end, quartz or quartz + mullite was produced. Because quartz and mullite formed only used FeCl2 for a liquid phase starting material, an effect by Fe3+ is suggested.

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Syntheses of Cr-doped YAG were performed by flux method. Obtained crystals were examined by stereoscopic microscope and electron scanning microscope. The crystal data obtained by 4-circle diffractometer are reported.

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We synthesized single corundum crystals by the flux method and added impurities to observe crystal form.We used Li₂O-MoO₃ flux and had good effects when flux composition was Li₂O:MoO₃=1:2 mole and Al₂O₃ added 5wt% of the flux and maximum temperature was 1050°C. Synthesized crystals developed c (0001) face, r (10-12) face and n (11-23) face. Synthesized crystals added impurities developed c face, r face and n face.

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 Single crystals of MgSiO₃ orthopyroxene with small amount of Al, Ca or Fe(3+) are grown using a flux of the Li₂O-MoO₃-V₂O₅ system. The orthopyroxene with small amount of Ca show the phase transition between LT-Opx and HT-Opx at 1150 C by high temperature in-situ X-ray diffraction experiments. In the orthopyroxene with small amount of Fe(3+), both Ppx and LT-Opx phases are observed. The chemical composition of Ppx is different from that of LT-Opx.

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Combined measurements of ultrasonic interferometry, in situ synchrotron X-ray diffraction, and X-ray radiographic techniques in a large-volume Kawai-type multi-anvil apparatus were made to estimate the P and S wave velocities and densities of NaCl up to 12 GPa at 300 K, and up to 8 GPa at 473 and 673 K.  The measured sound-wave velocity and density data at 300 K were used to derive the 300 K equation of state (EOS) by a least squares fit to the fourth-order Birch-Murnaghan finite strain equation, without pressure data.  A high-temperature and high-pressure EOS of NaCl was then developed using the Mie-Gruneisen relation and the Debye thermal model.  Our EOS model accurately modeled not only the present measured sound-wave velocity and density data, but also the previously reported volume thermal expansion and the temperature dependence of K_T, both at 0 GPa.

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It is widely accepted that (Mg,Fe)₂SiO₄ ringwoodite is a major constituent mineral in the mantle transition zone. High-temperature heat capacity data of Mg₂SiO₄ ringwoodite measured by previous studies are not consistent with those by theoretical calculations. In this study, it was remeasured by the differential scanning calorimetry in the temperature range of 300-850 K. The present heat capacity shows 3%-5% larger value than those observed by the previous studies. Re-examination of the thermodynamic stability of Mg₂SiO₄ ringwoodite at high pressures and high temperatures will be needed.

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 We developed a technique for the ab initio calculation of the lattice thermal condutivity, and applied it to MgSiO₃ perovskite and post-perovskite at deep mantle conditions.

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We used the first-principles molecular dynamics method to determine elastic properties of CsCl-type FeSi up to high pressures and high temperatures. The density of FeSi is lower than that of pure hcp-iron at inner core conditions. Both the compressional and shear wave velocities of FeSi are higher than those of iron. The density and compressional wave velocity of the inner core inferred from seismology is in good agreement with the simple model of the mixture of iron and FeSi. However, the calculated shear wave velocities of iron and FeSi are significantly higher than that inferred from seismology.

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Recently, we found that the perovskite-postperovskite transitions occur in CaRuO3, CaRhO3, NaNiF3 and NaCoF3 at high pressure. We investigated on crystal-chemical characteristics of the perovskite-postperovskite transitions in ABX3 compounds including the above compounds. Based on the data, we discussed that NaNiF3 is a good quenchable, low-pressure analogue to study the perovskite-postperovskite transition of MgSiO3 which occurs above 100 GPa.

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The isostatic compression of cordierite revealed a displacive phase transition occuring at 7 GPa accompanied by a orthorhombic-to-triclinic symmetry breaking. The static elasticity of the orthorhombic low-P form of cordierite is evidences anomalous softening as indicated by the pressure derivative of the bulk modulus (dK/dP = -0.6) on approaching the critical transition pressure between 6.9 and 7.4 GPa. In-situ XRD and Raman spectroscopy reveal that the compression is independent on the pressure media, and molecular species in the structural channels remain unchanged. The study in the DAC shows that neither P-induced de- nor overhydration occurs under the given pressure conditions. 

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In the present study, precise XRD measurements of brucite show that the c-axis of Mg(OH)₂ linearly decreases down to 99.7 % with increasing deuterium content. Diffusion profile measurements of the recovered sample from 1.8 GPa and 300 °C tentatively clarified that the H-D interdiffusion coefficient (D_H−D) is on the order of 10⁻¹⁵ m²/s. It was also clarified that the D_H−D in Mg(OH)₂ is larger than that in Mg(OD)₂. The dependencies of hydrogen isotopic ratios on the c-axis length and the H-D interdiffusion coefficient would be caused by different eigen values between OH and OD stretching vibrations along c-axis.

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In situ creep strength measurements on hydrous wadsleyite were conducted at 15-16 GPa and 1400-1700 K using a deformation-DIA apparatus in order to investigate water weakening of wadsleyite. The creep strength of wadsleyite decreased with increasing water content and temperature. The results suggest substantial heterogeneity in viscosity at the upper part of the mantle transition zone.

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High pressure and temperature experiments of Mg₂SiO₄-H₂ and MgSiO₃-H₂ samples have been carried out to clarify effect of H₂ fluid on phase relation in MgO-SiO₂-H₂ samples and to characterize silicate composition dissolved in H₂ fluids from 2.5 GPa, 1400 K to 15.0 GPa, 1600K using laser heated diamond anvil cells. The phase relations was clarified by X-ray diffraction measurements, Raman spectroscopy, electron microscopic and transmission electron microscopic observation indicated that forsterite and enstatite was decomposed in Mg₂SiO₄-H₂ and MgSiO₃-H₂ samples, respectively. These phase were dissolute into H₂ fluid incongruently.

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Knowledge of element diffusion is important for accurate understanding of material transport in the Earth’s mantle. To investigate diffusivity of elements in forsterite, we performed growth experiments of forsterite reaction rim at 7.4 GPa and 1673 - 1873 K using a multi-anvil apparatus. As a result, we found that Si is the slowest diffusing element at all studied experimental conditions. Therefore the diffusion rate of Si is the slowest in olivine at the conditions up to ~200 km depth, and the creep of olivine in the Earth’s mantle is considered to be rate-limited by Si diffusion.

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    Crystal elastic constants of Cmcm-CaIrO₃  was determined by inelastic X-ray scattering. The resulted elastic constants are tabulated as 6x6 matrix. The results was compared with previous theoretical calculation and compression experiment in DAC.

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We measured the P-wave velocity of hcp-Fe up to 167 GPa at room temperature and up to 1000 K at 62 GPa by using the inelastic X-ray scattering. The measurement at high pressure was made using the diamond anvil cell at the high resolution inelastic X-ray scattering beamline BL35XU, of Spring-8. We observed that the relation of P-wave velocity and density (Birch's law) at room temperature and high temperature follows the same single line, suggesting a negligible effect of temperature on the Birch's law.

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Valence of metal ions in inclusions in diamonds can give a direct clue to the redox condition of the deep mantle. This study is aimed to clarify the relationship between oxygen fugacity and Cr²⁺ contents in synthetic ferropericlase samples which were prepared under controlled fO₂ conditions. Cr-K edge XANES spectra indicated that the Cr²⁺ ratio to the total Cr was constant to the fO₂ from -7 to -11. The obtained results suggest that the presence of Cr²⁺ in inclusions in super-deep diamonds cannot be a direct indicator of redox state in the deep mantle.

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It is unclear whether separation of the crustal material from subducting slab near 660 km depth occurs because plastic strength of related materials at the deep mantle conditions has not been known. We conducted deformation experiments at pressure of ~17 GPa and temperature of 1473-1673 K using SPEED-MkII-D installed at BL04B1, SPring-8, Japan. Majorite (Mj) and ringwoodite (Rw) were deformed uniaxially under same temperature, pressure and stress conditions. An extrapolation of the experimental results to realistic strain rate in the mantle suggests that the separation of the oceanic crust component may not occur near the 660 km discontinuity.

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We have performed simple-shear deformation experiments of olivine at 7.2−9.6 GPa and 1400−1770 K. The A-type olivine fabric was developed under water-rich conditions, while B-type fabric was observed under moderately wet conditions. Only A-type olivine fabric can explain the vertical mantle flow which associates the seismic anisotropy of V_SH/V_SV < 1 in the deep upper mantle (> 200 km depth). A strong anomaly of V_SH/V_SV < 1 observed in the deep upper mantle beneath the East Pacific Rise is well explained by the distribution of water-rich regions (in which A-type olivine fabric is dominantly developed) in the deep upper mantle and upwelling mantle flows.

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In order to investigate the transportation process of water into the Earth’s interior, we investigated the elasticity of antigorite, chlorite, and talc by the first-principles calculation. We confirmed that trench parallel polarization anisotropy can be produced by the lattice preferred orientation of these hydrous minerals. We also found that the polarization direction is drastically changed by tilting the foliation plane and the trench normal fast polarization observed in the back-arc region can also be explained by the preferred orientation of these minerals.

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To investigate the effect of basicity to structural and physical properties of silicate liquid under high pressure, we performed molecular dynamics (MD) simulation of CaO-SiO2 liquid at pressure up to 6GPa. The self-diffusion coefficients of Si and O atoms in basic liquid decrease with increasing pressure. However those in acidic liquid increase with increasing pressure from several giga pascals. The basic liquids mainly act like ionic liquid. However, in acidic liquids, diffusion mechanism of Si and O atoms becomes network reconnection, and is enchanced under high pressure by distortion and increase of degree of freedom of –Si-O- network.

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Structure of hydrous SiO₂ glass was studied by X-ray diffraction method up to 7 GPa at ambient temperature. Structure factor S(Q) and radial distribution function D(r) of hydrous glass changed gradually with pressure up to 7 GPa at 300 K. Pressure variations in S(Q) is the same as those of dry SiO₂ glass. Decrease of Si-Si distance with pressure could accounts for these variations. The FSDP of hydrous SiO₂ glass also shift toward higher Q with pressure, as shown in dry one.

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The neutron camera of the custom-made product by Toshiba Corp. was introduced in J-PARC BL11 "PLANET" beamline on December 22, 2011. In this talk, we will present the outline of the neutron camera, and report the result of the preliminary experiment conducted in J-PARC BL-11 “PLANET” beamline.

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In order to study the effects of spin transitions on the equation of state of Mg-perovskite, we performed in situ synchrotron X ray powder diffraction on Fe³⁺-bearing Mg-perovskite using NaCl or Ne pressure medium. The sample was annealed in measurements using Ne pressure medium, whereas it was not annealed in the runs using NaCl pressure medium. The unit cell volumes of runs using Ne pressure medium are smaller than those using NaCl pressure medium. The difference in compression curves may be caused by the difference in stress conditions and/or Fe²⁺/Fe³⁺ ratios of the samples during the experiments.

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Viscosity of CO2-bearing silicate melt has been investigated at high pressures and high temperatures. We adopted X-ray radiography viscometry. Expeeriments were performed at KEK, Tsukuba, Japan.

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To verify previous reports of various anomalies in high-pressure ice VII and VIII at 10-15 GPa, proton conductivity has been measured up to 40 GPa. It increases first with pressure, takes a local maximum at 10 GPa, which is greater by the one order of magnitude of that of 3 GPa, and then decreases. Reverse of its pressure dependence at 10 GPa can be described by a change of its rate-determining process from jumping to rotation of protons. These results urge reconsideration of conventional phase diagram of ice and also lead to understanding evolution and dynamics in deep ice planets.

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The author developed a software code simulating a two-dimensional diffraction pattern. To find the orientation distribution and the lattice strain, a fitting procedure is incorporated into the code as follows: The software initially generates a large number of crystallites with random orientation under a strain-free condition, evaluates the residual of the simulated/observed patterns, and then iteratively modifies the orientation distribution and stress condition. By repeating the iteration step many times, the simulation seems to converge to a certain condition. The fitting procedure was applied for several actual diffraction patterns and its validity was confirmed. 

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Associated with halloysite, rhabdophane occurs during weathering of granite. The Sm/La ratios and the Eu anomalies (Eu/Eu*) of rhabdophane have negative correlation with the Ce anomalies (Ce/Ce*). Cerium(III) oxidative fractionation depends on path length from source minerals to rhabdophane. With the fractionation, HREE enrichment in rhabdophane is simultaneously facilitated by adsorption/desorption reaction on halloysite. Rhabdophane containing well-fractionated Ce can give constraints on redox conditions of ancient atmosphere.

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The structure of polygonal halloysite has been investigated mainly using HRTEM, as well as other analytical techniques. The specimen was from Olkhon Island on Baikal Lake, Russia. FE-SEM observation showed that most halloysite tubes have a variety of polygonal cross-sections. Cross-sectional TEM observation found a regular eighteen-faceted polygonal tube. HRTEM using a minimum-dose system revealed the stacking structure of the polygonal halloysite. The layer orientation is generally that with the (110) plane of the kaolinite layer perpendicular to the tube axis. The layer displacement is a random mixture of t₁ and t₂ shift.      

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Atmospheric oxygen evolution in the Paleoproterozoic is thought to be related with the glaciation events, which are thought to be induced from the transition of greenhouse effect gases (CO₂ and methane). But quantitative estimation of these crucial gases (O₂, CO₂ and methane) has not been sufficient. We analyzed the Paleoproterozoic paleosols and estimated the atmospheric CO₂ and O₂ at the same time, because Fe behavior in paleosols can reflect both of CO₂ and O₂. The results suggest that CO₂ in the Paleoproterozoic might have fluctuated reflecting the glaciation events while O₂ increased gradually as suggested by Murakami et al. (2011).

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Darhad basin in northern Mongolia is located in the continent where is sensitive to the climate change. It has been reported that several hydrologic events with climate changes occurred in this area. Darhad basin had been formed ice dam lake by Pleistocene glaciers. It is expected that lake sediments from Darhad basin would have record of climate change.  We tried to reconstruct evolution of water chemistry of the paleo-lake from mineralogical analyses.

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We have tried to estimate the differential compressive stress to drain the confined water between mica surfaces using the first-principles electronic state calculations based on the density functional theory (DFT) and thermodynamics. The results implied that approximately 1 GPa of the differential stress was needed to drain the monolayer water confined between mica surfaces.

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In the Earth's surfaces, rock pores often become unsaturated and the thickness of water on pore surfaces under unsaturated condition becomes less than that under saturated condition. Dissolution experiments were conducted using a porous rhyolite under saturated and unsaturated (water saturation 43%) conditions, and almost the same dissolution rates were obtained. Therefore, although 57% of pores were filled with air, almost all pore surfaces were wet and dissolution progressed. The estimated thickness of water film was 3-220 nm, and a film water of this thickness had an effect to progress weathering at a rate similar to that under the saturated condition.

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R​o​c​k​s​ ​a​b​o​v​e​ ​w​a​t​e​r​ ​t​a​b​l​e​s​ ​a​r​e​ ​​u​n​s​a​t​u​r​a​t​e​d​,​ ​w​h​e​r​e​ ​w​a​t​e​r​ ​a​n​d​ ​a​i​r​ ​c​o​e​x​i​s​t​ ​i​n​ ​p​o​r​e​s​.​ ​W​e​t​t​i​n​g​ ​f​i​l​m​ ​o​n​ ​m​i​n​e​r​a​l​ ​s​u​r​f​a​c​e​s​ ​p​l​a​y​s​ ​i​m​p​o​r​t​a​n​t​ ​r​o​l​e​ ​o​n​ ​m​a​s​s​ ​t​r​a​n​s​p​o​r​t​ ​a​n​d​ ​m​i​n​e​r​a​l​-​wa​t​e​r​ in​t​e​r​a​c​ti​o​n​.​ ​It​ ​i​s​ ​e​s​s​e​n​t​i​a​l​ ​t​o​ ​p​r​e​d​i​c​t​ ​w​e​t​t​i​n​g​ ​f​i​l​m​ thickness ​a​n​d​ ​u​n​d​e​r​s​t​a​n​d​ ​the f​a​c​t​o​r​s​ ​a​f​f​e​c​ting​ ​the ​t​h​i​c​k​n​e​s​s​.​ ​T​h​e​ ​​f​i​l​m​ thickness is controlled by​ ​v​a​n​ ​d​e​r​ ​W​a​a​l​s​'​ ​f​o​r​c​e​ ​an​d​ ​t​h​e​ ​f​o​r​c​e​ ​due to​ the ​e​l​e​c​t​r​i​c​a​l​ ​d​o​u​b​l​e​ ​l​a​y​e​r​.​ ​We considered the rocks differing in pore size distribution, and predicted how film thickness changes as drying proceeds using DLVO theory. It was revealed that the change trend of film thickness depends on the broadness of pore size distribution.

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Monohydrocalcite (MHC: CaCO3·H2O) is rare mineral in geological settings. The rare occurrences indicate MHC forms in unique environmental conditions in nature. It is well known that the formation of MHC requires magnesium in the solution. In present study, the systematic syntheses experiments from CaCl2-MgCl2-Na2CO3 solutions were performed to reveal the formation conditions of MHC, and to clarify the role of magnesium on MHC formation.

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Monohydrocalcite (MHC) is metastable phase of calcium carbonate. In laboratory, synthesized MHC is reported to change into calcite or aragonite during a days. On the other hand, the formation of MHC was observed the sediment of several hundreds of thousand years ago in the Lake Hovsgol. The attenuated total reflection infrared spectroscopy (ATR-FTIR) enables to observe molecular information of mineral at condition suspended mineral in solution. This study aims to observe the transformation processes of MHC in situ by using ATR-FTIR.

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The mineral which affects the migration of the element in earth’s surface environment was not only thermodynamically stable, but the metastable phase plays important role as an adsorbent and a transporter. Although the metastable phase transform to more stable phase with time, there are few studies about re-distribution of element during transformation of metastable phase. We conducted uptake experiments of lead ion on monohydrocalcite as metastable mineral to examine change in sorption behavior of lead ion during transformation of monohydrocalcite to aragonite in the laboratory experiments.

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In the last year, we have reported that a travertine calcite from a hot spring near Yellow Stone National Park contains a considerable amount of sulfur (S/Ca atomic ratio ~ 0.06) and the calcite crystal shows c-type super-reflections in the electron diffraction patterns. The chemical species of sulfur was identified as SO₄^2- by XPS analysis (Kim et al., 2011). In the present study, to find the model of SO₄^2- incorporation in calcite, we have performed the synthetic experiments of calcite.

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