Ruby-bearing leucocratic dike has been reported in meta-peridotite in Ray-Iz ophiolite, the Polar Urals. The leucocratic dike mainly composed of plagioclase, phlogopite, ruby and chromian spinel. Ruby is always surrounded by minute chromian spinel and paragonite, which contains minor amount of CaO (< 3.0 wt.%). We discuss the origin and formation process of the leucocratic dike based on the petrological and geochemical data, and try to estimate P-T trajectory of the host Ray-Iz peridotite massif.

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X-ray interference correction methods in quantitative electron probe microanalysis (EPMA) are validated to understand their accuracy and robustness. X-ray interferences by Th and Y are validated in this study using synthetic standard materials. X-ray intensity based method, calculating the interference factor directly from X-ray intensities, is sensitive to the mass attenuation coefficients of target material. On the other hand, chemical composition based method, calculating the factor from corrected chemical compositions, is less sensitive to the m.a.c.s of the target material.

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In order to elucidate the provenance of clastics in the Samarka Belt in Far East Russia, we investigated zircon U-Pb ages using the LA-ICP-MS and monazite U-Th-Pb chemical ages by EPMA. Result of dating of detrital zircons in the meta-sandstones from the southern Samarka Belt show almost bimodal in age distribution, 160-300 and 1900 Ma. they are thought to be from the North China Craton. On the other hands, in the northern Samarka Belt, detrital monazite has different pattern, i.e. strong peak at 500Ma, they are thought to be from the Khanka belt or its equivalent.

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Tomography non-destructively provides 3D internal structures and external form of objects. Recently, various tomography methods, synchrotron x-ray CT (SR-CT) and transmission electron microtomography (TEMT) and so on, were proposed. In the present study, we report the sample preparation method using focused ion beam (FIB) toward the high spatial resolution seamless tomography from micrometer (SR-CT) to nanometer scale (TEMT).

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JAMSTEC manages a collection of marine rock samples obtained by JAMSTEC research vessels, and provides these samples to public requests with scientific/educational purposes. Through the “GANSEKI” database, researchers/educators can access to JAMSTEC rock samples and associated data. For the better usability, JAMSTEC is making efforts to provide closs-linked databases and visualized interfaces.

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  Magnetite in the Kohyama gabrro, Hagi, Yamaguchi Prefecture were analyzed by EPMA. It is rarely including some amounts of vanadium. So, mainly we report the V-content of their magnetite.

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  Very rare mineral fletcherite is firstly found in the Japan. It occur including chalcopyrite from sulfide rich layer in  Kohyama gabrro. The mineral mainly include the elements for Cu, Fe, Ni, Co and S.   Ni content is more than that of Co, the mineral correspond to fletcherite; Cu(Ni,Co)₂S₄.

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The Hishikari epithermal gold deposit, located in southern part of Kyushu, is well known as one of the largest vein type gold deposits in the world. Precipitation of ore minerals is related to boiling of hydrothermal fluid or mixing with meteoric water. The purpose of this study is to clarify the relation between ore-formming mechanisms and quartz texture by microscope obsevation at Shosen No.5 vein.

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Lece deposit is the epithermal type Pb-Zn deposit in southern Serbia.The main minerals in this deposit are sphalerite wurtzite and galena.Sphalerite and wurtzite are coarse grain and their chemical is almost pure ZnS and homogeneous.ZnS minerals include primary fluid inclusions.In this study, homogenization temperature and salinity of fluid inclusion was measured.Sulfer isotope geothermometry was applied to sphalerite(or wurtzite)-galena pair.Depth of mineralization, I will be discussed from above information.

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The aims of present study are: (1) to confirm whether the Fe concentration on dislocation core is a common phenomenon in deformed olivine grains of mantle-derived peridotite, (2) to clarify the exact mechanism of Fe concentration, namely Cottrell atmosphere or pipe diffusion. The main results are as follows: 1) Fe concentration on dislocation core in all the studied olivine samples is detected, which suggests that it is common phenomenon in mantle peridotite. 2) The mechanism of Fe concentration on dislocation core in olivine grains is preferably Cottrell atmosphere than other phenomena such as pipe diffusion.

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Chromitite samples from MAR 15°20’N FZ, ODP Leg 209 recorded high temperature metamorphism up to mid-amphibolite facies. The crystal orientation varies inside a grain with chemical modification of the metamorphism.

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It is generally considered that protoenstatite is unquenchable and not stable at room temperature. However in specimens generated by experiments, protoenstatite was sometimes observed at room temperature. The purpose of this study was to determine the necessary condition for protoenstatite can exist at room temperature particularly focusing on the grain size. We classified enstatites into various grain sizes and heated and cooled them. After that products were analyzed by XRD method. The results show protoenstatite can exist at room temperature in case of about 60μm below and a smaller protoenstatite can exist easily than a larger one.

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Calcic plagioclase in the Kaizuki-yama granite is reported.

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In this study, we report vertical profile of the shocked quartz grains to constraint the depositional processes of impactite of the YAX-1 core. We analyzed both the grain size distribution and planar deformation features (PDFs) on shocked quartz contained in the impactite of the YAX-1 core. We examined characteristics and vertical profiles of PDFs along with the YAX-1 core to discuss the excavation, transport, and depositional processes of each impactite unit of the YAX-1 core. We found that, in the middle part of impact melt layer (Unit 5), shocked quartz grains were dominated high shocked grains. These results suggest that unit 5 is likely to have been formed by an outward flow of impact melt-sheet from the transient crater cavity during the collapse of the central uplift and transient crater. In unit 1, i.e., the uppermost impactite unit, both the grain size and shocked quartz abundance profiles show cyclic variations in unit 1, which suggest water invasions into the crater.

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Cathodoluminescence (CL) spectroscopy of quartz grains in the Gobi desert sediments reveals the quantitative ratios of emission components derived from defect centers, which might characterize structural properties of the quartz. CL obtained from the quartz grains can be used as an indicator for their provenance and stratigraphic assignments among the sediments.

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The sediments provenance would give important information on the erosion processes, such as uplift of the mountains, suggesting the environments at the time of sediments transportation. When new procedures for clarifying provenance of such sediments are established, it will be useful to elucidate the provenance of sediments in the geohistorical environments.In this study, we report the characteristics of ESR / TL / SEM-EDS of natural quartz taken of various rocks and sediments, to discuss the possibilities of identifying sediments provenance.

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We report mineral compositions and characteristics of ESR of granitic rocks around Lake Biwa.

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Fission-track zircon dating using LA-ICP-MS was carried out for 4 pyroclastic flow deposit samples from the Late Cretaceous volcanic rocks in the Banshu-Ako area, southwest Japan. These samples are using zircon identical to U-Pb dating from previous study. The Hinase, Ako, Gomyo and Iwami Formations are determined to be 82.3, 86.1, 87.2 and 80.7 Ma, respectively. These results are identical within analytical error for the U-Pb dating, respectively.

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Slickenside is a smooth surface like a mirror formed on fault plane. In this study, we try to clarify 1) the formation mechanism of slickenside and 2) the influence of slickenside on faulting behavior. We observed slickenside developed at limestone along Glarus thrust and performed a series of experiments to simulate slickenside using Carrara marble. Our observations on natural slickenside reveal that slickenside has characteristic microstructures. Moreover, the simulation experiments indicate that the slickenside development affects the dynamic properties and has influence on subsequent fault movement.

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In order to confirm an expansion of eclogite unit, we have reexamined the metamorphic evolution of Sanbagawa metapelites in the Asemi-gawa region. In this study, we make attempt to estimate the metamorphic conditions of metapelites using a Raman geothermobarometer and thermodynamic calculation. Metamorphic conditions calculated from measured Raman carbonaceous-material geothermometer and quartz-Raman barometer were well matched with those from thermodynamic calculation for inclusion paragenesis. These results implied that the highly precise information at the progressive metamorphism is acquired by Raman geothermobarometer and petrological analysis.

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We attempted to investigate the detailed microstructures and crystallinity of Carbonaceous Material (CM) to understand the heterogeneity of recrystallization under low temperature condition. In case of structural change at around 400 degreeC, CM represents the heterogeneous microstructure and crystallinity at the boundary of fully ordered gaphite. These data suggest that  other influences strongly affect recrystallization of CM, and that is the reason why natural graphitization cannot explain thermodynamic relationship between peak temperature and duration of heating.

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We investigated the mineral assemblage changes within the lawsonite-blueschists in the Hakoishi sub-unit of the Kurosegawa belt in Yatsushiro area. Following mineral assemblages are observed in studied area from east to west; pumpellyite (Pmp) + Na-amphibole (Na-Amp), lawsonite (Lws) + Pmp + Na-Amp, Lws + Na-Amp + Na-pyroxene. Newly constructed petrogenetic grid in NCMASH system shows such changes are derived from pressure/temperature increase. Compositional changes of amphiboles and pyroxenes, in addition to above-mentioned assemblage changes, suggest that studied lawsonite-blueschist was a part of the oceanic crust subducted at the depth of 18-25km.

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Two generations of garnet have been identified from the kyanite garnet-amphibolite which occurs in the Tonaru metagabbro mass, Besshi district, central Shikoku, Japan. Kyanite-garnet amphibolites from the western parts of the Tonaru metagabbro mass are composed mainly of amphibole, zoisite, kyanite and garnet. Garnets are pyrope-rich in composition, increasing X_Prp (0.36–0.53) and decreasing X_Alm (0.44–0.32) from the core to the rim. Network-like micro-veins occur throughout the garnets which are filled by Fe-rich garnet. Micro-veins have a composition of almandine (X_Alm 0.43–0.53), and pyrope (X_Prp 0.24–0.39) with minor spessartine (X_Sps 0.02–0.07) components.

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The eclogite-bearing Alag Khadny metamorphic complex in the Lake Zone, SW Mongolia located in the central part of the Central Asian Orogenic Belt (CAOB), consists mainly of orthogneisses with large bodies of eclogites. Orthogneisses interleave with marbles which containing lenses of garnet-chloritoid schistsand and eclogite. Sometimes, vein-type orthogneisses developed in large eclogite bodies. Four metamorphic events [M1 (amphibolite facies), M2 (blueschist to eclogite facies) M3 (epidote-amphibolite facies) and M4 (amphibolite facies)] distinguished based on mineral assembalges developed in the eclogite bodies.  

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U-Pb dating and determination of REE pattern of zircon extracted from pelitic migmatite from the Aoyama area, Ryoke metamorphic belt have been done by SHRIMP. The result was 92.5 ± 0.5 Ma and 92.5 ± 0.7 Ma. Zircon includes several-μm-sized possibly melt inclusions between core and rim, and this part is dark in CL images. The REE pattern of zircon rim showed HREE-enriched pattern, suggesting non-equilibrium between garnet. The zircon rim also showed low Th/U ratio (<0.1) and LREE concentration, suggesting coexistence with monazite. This observation is consistent with the CHIME monazite age older than the zircon rim age.   

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Southwestern Group in Sri Lanka consists of lower grade metamorphic rocks. The detrital cores of zircon of garnet biotite gneiss are suggesting two possible Achaean sources. Overgrowths on the detrital cores of zircon shows two or three generation stages. Zircons in orthopyroxene-bearing gneisses show three sub-generations. Monazites in garnet-biotite gneiss show several internal textural domains.

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We propose the Ti-in-garnet geothermobarometer for ultrahigh-temperature granulites calibrated
from the experimentally reversed data of Ti content in garnet coexisting with orthopyroxene,
rutile and quartz at pressures 7–23 kbar and temperatures 800–1300 C. Titanium solubility in garnet is not so sensitive to the pressure change as compared with the temperature dependence.
  Applying the present geothermometer to Ti contents of garnets in the leucocratic garnet–
sillimanite gneiss in Lützow-Holm Complex and the orthopyroxene granulite from McIntyre
Island, Napier Complex, we evaluate the retrograde metamorphic conditions of these granulites
6.6 kbar/833 C and 10.3 kbar/928 C, respectively.

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The felsite inclusions recently found within garnet in granulites from continental collision orogens may necessitate changes to fundamental beliefs about exhumation and cooling rates of granulites. We estimated the cooling rate faster than those hitherto assumed for granulites by 3 orders of magnitude, using the spacings of coherent cryptoperthite lamellae of alkali feldspar in a felsite inclusion-bearing UHT pelitic granulite from Sri Lanka.

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To investigate effect of jadeite (Jd) on Fe-Mg distribution coefficient (K_D) between garnet and clinopyroxene, we studied eclogite collected from Donghai area in the Sulu UHP metamorphic belt. Here, we selected garnet and omphacite grains that are in direct contact with each other for analyses. On omphacite, a positive correlation between Jd content and Fe²/(Fe²⁺+Mg) was recognized. Here, by paring garnet rim and omphacite rim compositions, we calculated K_D. As a result, values of lnK_D decrease with increasing Jd contents. In fact, application of garnet-clinopyroxene geothermometer to these data shows that the calculated temperatures increased with increasing Jd contents.

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Paragonite-clinozoisite intergrowth was discovered as inclusions in garnets from the Sanbagawa pelitic schist of the garnet zone in the Kanto Mountains. The paragonite-clinozoisite intergrowth formed from lawsonite and albite during prograde metamorphism and the inclusion assemblage with additional phases of quartz, albite, phengite, chlorite, rutile, zircon, calcite and apatite suggests P = 0.8 – 1.2 GPa and T = 400 – 450 ˚C.

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The Tonaru metagabbro mass occurs as a large lenticular body in the Sambagawa metamorphic belt in central Shikoku, and it consists of two different lithologies. One is diopside amphibolites (T-I type), and the other is garnet epidote amphibolite (T-II type) accompanied by small amounts of eclogites. Garnet epidote amphibolites composed mainly of garnet, epidote, amphibole (pargasite), plagioclase (An 9-20) and quartz. Two types garnet have been identified from the garner amphibolites, i.e. coarse grained (3 cm), the other is fine grained(0.5 cm). Core to rim of the fine grained garnets suggests a prograde metamorphism.

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Eclogites in the Sebadani metagabbro mass composed mainly of garnet, omphacite, amphibole (Brs, Mg-Kt and Gln) and epidote. Garnet has a zoning with grey to black core, grey to black mantle and white rim in backscattered electron image. Omphacite is included in garnet, and it also occurs in the fractures in the garnet. Therefore, the garnet core was formed during first prograde stage, the mantle was formed during second prograde stage, and the rim was formed during the Sambagawa metamorphism.

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The metamorphic evolution of the kyanite garnet amphibolite from the western part of the Tonaru metagabbro mass can be divided into three metamorphic events. These are a first high-pressure metamorphic event (i) represented by high-Mg garnet and inclusions in the garnets (kyanite, zoisite, amphibole, phengite, chlorite and quartz), a second high-pressure metamorphic event (ii) recorded by the mineral assemblage of Fe-rich garnet, kyanite, zoisite, amphibole (Mhb, Ts), phengite and chlorite developed in the garnet fractures, as well as in the matrix. The third high-pressure metamorphic event (iii) is defined by randomly oriented phengites in the matrix together with epidote, chlorite, muscovite and plagioclase (An<18).

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Eclogites in the northeastern parts of the Seba eclogitic basic schists consist mainly of garnet, epidote, glaucophane, barroisite, omphacite, phengite and dolomite. Abundant dolomites suggest that the peak eclogite facies metamorphism is affected by CO₂ - bearing fluid. Estimated peak eclogite facies conditions (645-680 °C and 23-24kb) with variation X_CO2 (0.03-0.05) are similar to those of the second high-pressure metamorphic event of the Onodani eclogites (630-680 °C and 20-22 kb). This suggests that the considerable amounts of CO₂ are included in the fluid during the eclogite facies metamorphism.

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Exceptionally well-preserved lawsonite eclogite occurs in the southern Motagua fault zone, Guatemala. Texturally homogeneous lawsonite eclogite occurs as meter-scale blocks in serpentinite, and is well suited for phase-equilibrium analyses such as pseudosection modelling. In contrast, evidence for disequilibrium garnet crystallization is common in quartz-rich pressure shadows around eclogite boudins in metasedimentary rocks. Garnet in such domains shows a considerable variation in compositional zoning from grain to grain, and some grains show sector and reverse zoning.

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The Neldy Formation is mainly composed of garnet-phengite schists and chlorite-carbonate rocks metaquartzites, marbles, amphibolites and garnet amphibolites. Eclogites are preserved in the cores of the garnet amphibolite bodies. Three metamorphic stages have been distinguished from the texture and chemical composition of minerals of the chloritoid bearing schist from the Neldy Formation. The prograde to peak metamorphic stages is characterized by the core to the rim of the porphyroblastic garnet and inclusion minerals there and schistosity forming matrix minerals phengite, chlorite, chloritoid, rutile and quartz. The retrograde metamorphic stage is characterized by muscovite, chlorite and albite, which replacing chloritoid and garnet along the rim and cracks.

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We make attempt to calculate the metamorphic conditions using residual pressures of quartz and zircon inclusions in garnet porphyroblasts. We used the samples of high-pressure metamorphic rocks taken from the Sambagawa belt and of ultra-high-pressure metamorphic rocks from the Western Alps. The estimated metamorphic conditions calculated from measured residual pressures were well matched with those from thermodynamic models in high-pressure metamorphic rocks, while those in ultra-high-pressure rocks were not matched. Although further improvement is needed for ultra-high-pressure rocks, it is implied that the metamorphic condition can be constrained by Raman spectroscopy using quartz and zircon inclusions in garnet porphyroblasts.

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The Kurosegawa Tectonic Zone, which is characterized by serpentinite mélange in the Jurassic Chichibu Belt, is distributed from Kyushu to Kanto Mountains, SW Japan. We carried out regional-scale geological, geochemical and geochronological analyses on the blocks in serpentinite from Kyushu to Kii peninsula.

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The Sør Rondane Mountains (SRM), East Antarctica, has been considered to locate inside of the collision zone during amalgamation of the Gondwana supercontinent (e.g. Meert, 2003; Jacobs and Thomas, 2004). In this study, we conducted zircon LA-ICP-MS U-Pb dating and monazite EPMA U-Th-Pb dating for metamorphic rocks to obtain ages related to protolith formation and metamorphic ages, and also whole-rock chemical analysis to discuss the history of metamorphic rocks in the SRM. Our results indicate that Northeastern and Southwestern terranes composing the SRM showed the different origin and forming time of the protoliths, and collided each other at 620-650 Ma.

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This study highlights the necessity of integrating different spectral analysis data of zircon (SEM-CL and Micro-laser Raman spectral data) to assign the ‘proper’ event to high-resolution U-Pb age data for zircon recording multiple events of magmatism, metamorphism and metasomatic changes.

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3 types of Ca-amphiboles (Amp-Ia, Ib, S) showing different modes of occurrence were found from Nové Dvory UHP eclogite (4.5-4.9GPa, 1050-1150^oC; Nakamura et al., 2004). Amp-Ia appears with omphacite and/or rutile in Multiphase Solid Inclusions (MSI-Ia) sporadically occurring in garnet, Amp-Ib appears with diopside and/or spinel in MSI-Ib aligned in garnet, and Amp-S appears mainly with plagioclase in symplectite developed between garnet and omphacite. Minerals constituting MSI-Ia are euhedral, and those constituting MSI-Ib and S are generally anhedral. These facts indicate Amp-Ia crystallized together with garnet under high-pressure conditions, and Amp-Ib/S crystallized under low-pressure conditions due to fluid infiltration.

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 In the Kasagi area, Kyoto, Ryoke metamorphic rocks are overprinted by the contact metamorphism by the Younger Ryoke granites. In the low-temperature part of the sillimanite zone, andalusite without sector zoning is subhedral, and its long axis is weakly aligned. This suggests regional metamorphic origin, because the mode of occurrence contrasts with the contact metamorphic andalusite with sector zoning and random orientation. Sillimanite in the same region is found as veins or networks cutting the gneissosity. Thermodynamic calculation permits acidic fluid to dissolve plagioclase and biotite to form sillimanite. These sillimanite are the result of fluid infiltration from the granites.

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In order to apply a quartz-Raman barometer to ultra-high pressure rocks, we verified the features of residual pressures of quartz in garnet. The samples were ultra-high pressure metamorphic rocks taken from the Sulu belt, eastern China. As a result of this study, it is obvious that quartz retained different residual pressures according to the position where garnet is included. On the other hand, coesite was not observed in garnet. It is implied some possibilities that the phase transition of quartz-coesite did not occur because quartz in garnet was included before reaching the stability field of coesite.

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