We found the osumilite and the spinel + quartz coexistence within the garnet porphyroblast in the garnet-sillimanite-quartz granulite from Rundvagshetta, Lutzow Comlex, East Antarctica. We will disscuss the metamorphic path of this area from the new evidence.

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We analyzed zircon grains from rock samples of EGB using U-Pb SHRIMP method to clearly document these thermal events that can also used as well-constrained tools for Indo-Antarctic correlation. Zircon grains in UHT aluminous granulites from the central part of EGB show detrital cores surrounded by oscillatory-zoned mantle, which possibly is magmatic in origin. Thick low CL rim (U-rich) suggests a metamorphic origin. Simple concentric zoned zircon also shows similar CL character as the metamorphic rims. While the detrital cores suggest near-concordant age of c. 1760+15 Ma for one sample, discordia lines show upper intercept ages at 1589+34 Ma, 1627+49 Ma and 1821+59 Ma respectively in other samples.

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We have dated various granitoids from the Archaean Ntem complex, southern Cameroon by the SHRIMP zircon U-Pb method to define the magmatic evolution in the northwestern part of Congo craton. CL imageries of zircon grains collected from charnockites together with their Th-U composition and thin section observations clearly vindicate their magmatic origin. These zircons yielded magmatic ages of 3382 ±21Ma, 3266 ±5 Ma and 3062 ±15 Ma. Our data clearly suggest that the charnockite magmatism in the Ntem complex started earlier than ca. 2900 Ga as proposed previously. On another hand, xenocrystic zircon from a granite collected from the northern zone of the complex exhibit an early Mesoarchaean inherited age of 3477 ±16 Ma, the oldest age ever reported from the Congo craton, while majority of zircons in the same rock yield magmatic age of 2853 ±12 Ma. These features collectively support the existence of an early Mesoarchaean crust in the Congo craton.

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Characterizing HT/UHT granulite facies processes provides crucial information in understanding P-T-fluid regime of crystallization and subsequent modification of mid-to lower continental crustal blocks. Southern Madagascar always remains in international focus from the fact that rocks of this belt expose deeply eroded crust during the Pan-African orogen that amalgamated the continental blocks of Gondwana supercontinent during Cambrian time. Despite this immense significance, detailed petrological investigation in this terrane is meager. This is particularly critical because high-grade rocks of this terrane are associated with melt phase showing variable extent of rock-melt/fluid interaction. Melt-solid coupling and decoupling can explain variability of mineral parageneses in such a terrane. Metapelite, granite gneiss and anatectic migmatite are well-exposed in the south of Ranotsara Shear Zone, southern Madagascar and make this an excellent study area for assessing the P-T-fluid evolution, role of partial melting, the oxygen and water buffering during metamorphic/anatectic processes. Metapelites preserve peak mineral assemblages Grt-Sil-Spl-Crd-Pl-Qtz and Opx-Grt-Sil-Spl-Crd-Pl-Qtz around the Ranotsara Shear Zone and in a central part of the Betroka Belt, respectively. These two different peak mineral assemblages probably reflect the difference of the crustal level (baric difference), superposition of later imprints or merely resulting from bulk rock chemical control associated with melt activity and fluid-buffering. Therefore, this study aims to probe petrological relationships and ascertain P-T conditions in the southern part of Ranotsara Shear Zone. This also emphasizes the nature and extent of melt/fluid-rock interaction. We have constrained the role of the oxygen and water as buffering media that have a profound effect on the stability of the mineral assemblages in the studied area during the metamorphic processes.

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Metamorphic condition of a mafic granulite from the Nomamisaki metamorphic rocks, southern Kyushu, was obtained as 780°C and less than 5.8 kbar.

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The Garnet-Kyanite-Staurolite gneiss was observed from the Pangon metamorphic complex within the Shyok suture zone in Ladakh Himalaya. Mineral chemistry by EPMA and Laser RAMAN analysis was carried out based on microstructure of rocks. Garnet shows microstructural evidence of two distinct stages. The garnet core is extremely Mn-rich with a resorbed grain boundary. The core is over grown by Mn-poor garnet, which preserves euhedral shape. The garnet bearing domains are always associated with leucosome. This suggests a peritectic garnet growth. The phase analyses in Mn-NCKFMASHT system are carried out for the Mn-rich Grt core and Mn-poor Grt rim bearing assemblage. The result indicates a clear increase of P and T along the prograde segment. Sil absence suggests a Hairpin type clockwise P-T trajectory.

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Eclogites, garnet amphibolites and country rock gneisses have been described from the Aktyuz complex in the Zaily Range of the Northern Tien-Shan, Kyrgyzstan. The textural relationship among minerals and mineral chemistry of the eclogites, garnet amphibolites and country rock gneisses in the Aktyuz Formation suggest three distinct metamorphic events. The first MP-HT metamorphic event of the amphibolite/epidote-amphibolite facies conditions (T=560-650C, P=4-10 kbar), the second HP-LT metamorphism with the prograde stage of the epidote blueschist facies conditions (T=370-570C, P=8-18 kbar) to the peak eclogite facies conditions (T=600-710C, P=15-25 kbar) and retrograde stages of the epidote amphibolite facies conditions (T=460-580C and P=7-12 kbar), and the third HP-HT metamorphic event with the prograde and peak metamorphic conditions of T=550-670C; P=7-11 kbar and T=695-770C and P=13-14 kbar, respectively. In the country rock gneisses, the prograde stage of epidote-amphibolite facies (T=460-480C and P=7-9 kbar) and the peak P-T conditions (T=670-760C and P=13-15 kbar) are recognized. The estimated P-T conditions for the prograde, peak and subsequent retrograde stages in garnet amphibolites and country rock gneisses are almost identical, which implies that the third metamorphic event in the eclogites and garnet amphibolites is equivalent to the first metamorphic event in the country rock gneisses. The third metamorphic event probably results of collision tectonic processes in the country rock gneisses.

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Stp Group

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Chemical compositions of minerals and whole-rock Sr isotopic composition of the Shikanoshima basic rocks, distributed in the Shikanoshima Island, northern Kyushu, have been determined. Compositional change of small hornblende in coarse-grained gabbro is differs from that of big hornblende, and resemble that of hornblende in medium-grained quartz diorite. Clinopyroxenes has similar chemical composition to that in high Mg diorite in northern Kyushu. Initial Sr isotopic ratios of coarse-grained gabbro and medium-grained quartz diorite overlap each other. The occurrence, whole-rock and mineral chemistry and Sr isotopic composition of the Shikanoshima basic rocks suggest that migration of big hornblende crystals at formation of medium-grained quartz diorite and chilled margin caused unusual texture of cause-grained gabbro.

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We report new petrographical and geothermobarometric data of Hida metamorphic rocks from the Odori-gawa area in Gifu Prefecture, central Japan. The major lithologies in this area include Grt-Hbl gneiss (Grt+Hbl+Kfs+Chl+Qtz), Grt-Bt gneiss (Grt+Bt+Mc+Pl+Kfs+Ep), Hbl gneiss (Cpx+Hbl+Pl+Mc+Chl+Spn) and Ca-Amp-Bt gneiss (Ca-Amp + Bt + Pl + Ilm + Qtz). P-T conditions were estimated using Grt-Hbl, Grt-Bt and Hbl-Pl geothermometers and geothermobarometer of Al2O3-TiO2 isopleth of Ca-Amp to be 720-850 °C and 0.5-0.9 GPa, which correspond to the highest P-T condition so far reported from this locality. The results suggest a clockwise P-T trajectory from the high-pressure stage to granulite-facies high-temperature stage, followed by retrograde amphibolites-facies event.

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Middle to lower crustal section of Paleozoic oceanic island-arc exposes in the Yakuno ophiolite at the Asago area, Asago body, southwest Japan. This ophiolitic body is composed of mafic metamorphic rocks and basic to felsic intrusive rocks. Field occurrences and geochemistry suggest that the mafic metamorphic rocks are originated from gabbroic rocks derived from oceanic basin. On the other hand, the intrusive rocks are clearly of island arc affinity, and composed of hornblende gabbro, quart-diorite, quartz monzodiorite, tonalite and granodiorite. Previous work by Suda (2004) presented that mafic migmatite occurs at the lower crustal level of the Asago body which might represent the anatexis of mafic lower crust under the oceanic island-arc. Moreover, morphological changing of migmatite toward the upper level might represent the accumulation and segregation processes of the anatextic melts. On the basis geochemical modeling and petrography, in this work, we demonstrated that the intrusive rocks in the Asgo body are all originated from the partial melts by dehydration melting and/or water-saturated melting of mafic middle to lower crust: tonalitic leucosome in the migmatite area represent the partial melt produced by the water-saturated melting of lower crustal level of mafic rocks, while intrusive rocks occur as dyke and shill in the mid crustal level represent the residual melt or cumulate by the fractionation of plagioclase and hornblende from the partial melts produced by the dehydration melting of middle to lower mafic crust. These occurrences observed in the Asago body probably representing the earliest stage of the generation of andesitic continental crust by partial melting of basaltic lower crust.

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Argon closure system of phengites in a whole metamorphic sequence, which has been deformed during the exhumation and the cooling of rocks, is controlled by the onset of brittle deformation in the low-grade sequence. The onset of brittle deformation depends mainly on the strain rate of deformation during the exhumation of metamorphic pile. The significantly different strain rates result in the contrasting age-temperaure-structural relations for two metamorphic sequences of central Shikoku and Kanto Mts.areas in the Sanbagawa belt, and Ishigaki and Nishiki areas in the Suo belt. The Tenryu area in the Sanbagawa belt shows an intermediate age-temperature relation, suggesting that the strain rates of the in situ Sanbagawa metamorphic sequence change systematically from the west to the east.

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Sillimanite is one polymorph of Al2SiO5 minerals. Carpenter (1985) suggested the possiblity of high temperature phase (Pbam) in sillimanite, which has Al/Si disorder in T sites structure. In the presesnt study, we observed the sillimanite in Mt. Riiser-Larsen, Napier Complex, East Antarctica, by transmission electron microscope. The TEM result show antiphase boundaries in the core of sillimanite. This result suggested that the this core arrive at high temperature.

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The first occurrence of eclogites in Mongolia has been described from the Chandman district in the Lake Zone, western Mongolia (Hanzl and Aichler, 2007; Takasu et al., 2008). Eclogites consist mainly of garnet, omphacite, Na-Ca amphibole and epidote with a small amount of quartz, albite, phengite, Ca-amphibole and rutile. Garnet occurs as subhedral to euhedral porphyroblast up to 10 mm across, and it shows a prograde zoning with increasing of Fe and Mg and decreasing of Mn and Ca from core to rim. The maximum pyrope contents at the rim of the garnet are c. 20 mol.%. Omphacite in the matrix is homogeneous and the the maximum jadeite contents are 42 mol. %. After the peak metamorphic conditions eclogite have experienced a prograde metamorphism of the amphibolite facies together with the surrounding gneisses.

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The Mashan complex lies in eastern part of the Central Asian Orogenic Belt, and comprises Al-rich pelitic rocks, felsic rocks and calc-silicate rocks, intercalated with meta-igneous rocks. The Al-rich pelitic rocks are sub-divided to Spl-bearing Grt-Sil schist, Spl-free Grt-Sil gneiss, Grt-free Sil schist and Grt-Crd-Sil schist. The Al-rich pelitic rocks have undergone amphibolites facies and granulite facies metamorphism. The peak P-T conditions are: T=800-825C and P=7.5-7.8kbar.

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⁴⁰Ar/³⁹Ar dating of the high-P/T metamorphic rocks of the Heilongjiang Complex in the Jiamusi Massif shows the plateau ages of 165 Ma and 171 Ma for pelitic schists; and isochron ages of 145 Ma and 146 Ma for blueschists. There are at least two stages of high P/T metamorphism for the Heilongjiang Complex approximately 170 Ma and 145 Ma.

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Monazites in garnet-chloritoid-talc schists from the Makbal complex were geochronologically analyzed. The garnet-chloritoid-talc schists were metamorphosed under the UHP conditions T>600 °C and P>25 kbar (Ishida, 2004; Bakirov, A.A., 2006). The mineral assemblage of the UHP stage is suggested as garnet + chloritoid + talc + phengite + rutile + coesite + glaucophane + florencite + monazite + apatite. A garnet occurs as porphyroblasts up to 1.5 cm across and it contains mineral inclusions of chlorite, chloritoid, talc, phengite, quartz, coesite, apatite, rutile and opaque minerals with scarce amount of monazite, florencite, phlogopite and paragonite. The garnet porphyroblasts including monazites show a texture of prograde growth. The garnet-chloritoid-talc schists are retrograded from the peak pressure conditions in the coesite stability field to the greenschists facies conditions through the epidote-amphibolite facies. The ages of monazites are obtained by CHIME Th-U-Pb method (Suzuki et al., 1991; Suzuki and Adachi, 1991), using a JEOL JXA-8800 electron microprobe with 4ch wavelength-dispersive X-ray analytical system (WDS) installed at the Department of Geoscience, Shimane University. The age of monazites separated from garnet-chloritoid-talc schist is 484+/-28Ma. The age of monazites in thin section of the same sample, which occur in the matrix together with talc, phengite and chloritoid is 458+/-76Ma. These two ages are the same within the error. The combination of these two data gives an age of 481+/-26Ma (Takasu et al., 2006). The CHIME age of 470+/-100 Ma of monazites included in garnet porphyroblasts have been obtained. The monazites included in garnets probably coexist with coesite, chloritoid, talc, phengite and rutile, and the age is timing the UHP metamorphism. The age of 481+/-26Ma is the same as the age of monazites in garnet, and therefore it is the age of the UHP metamorphism.

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The Hundar igneous complexes in the Shyok suture zone, Ladakh Himalaya consist of granite, diorite and dykes of andesite and leucogranite and have intruded into the sedimentary sequences in the suture Zone to form the contact aureole. EMP analyses of the constituent minerals reveal that the Ladakh batholiths and Hundar igneous rocks are calc-alkaline and formed in a subduction related tectonic setting. K-Ar analyses of biotites revealed that the subduction related igneous activity in Ladakh-Shyok area took place at least for 16Ma, from 50Ma to 66Ma, before the collision event between the Indian and Asian plates.

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The remnant strain of quartz inclusions in garnet can be used as a sensitive indicator of formation pressure. New Raman analyses document low remnant strain in quartz inclusions in an area adjacent to the Higashi-akaishi peridotite body in Sanbagawa belt. These results imply equilibration in the epidote-amphibolite facies conditions and disagree with independent petrological and structural studies that suggest this area lies within the eclogite unit. The host garnet for the low strain quartz inclusions characteristically shows a composite chemical zoning indicating a resorption followed by an overgrowth. The breakdown of garnet during exhumation and consequent pressure release of quartz included under eclogite facies is a possible explanation for the local decrease in remnant strain and can account for the chemical zoning.

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CL images of albite (Ab₉₉Or₁) exhibit CL halo in the surface of ⁴He⁺ ion implanted samples. Approximately 15 micro meter width of CL halo might be consistent with theoretical range of alpha-particles from disintegration of ²³⁸U in feldspar. CL image and CL line analyses indicate that CL intensity of albite gradually increases from the implantation surface to the inside up to approximately 15 micron meters. CL spectra of albite exhibit a spectral peak at 620 nm, which can be assigned to radiation-induced luminescence center. Its CL intensity caused by ⁴He⁺ ion implantation has a positive correlation with radiation dose. This fact implies that CL of albite could be used to evaluate the radiation dose in a geological environment as a geodosimeter.

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Vapor-liquid partitioning coefficients for Cu and Zn in aqueous fluid were determined under boiling conditions at 500-650°C and 35-100 MPa in sulfur-bearing and sulfur-free systems. A synthetic fluid inclusion technique was used to sample the experimental system coexisting vapor-rich and liquid-rich fluid inclusions, with the Cu and Zn concentrations in individual fluid inclusions then analyzed by synchrotron radiation X-ray fluorescence. The vapor-liquid distribution constant of Cu (KD = mCu(vapor)/mCu(liquid)) is found to be strongly dependent on the sulfur content in the experimental solutions. In sulfur-bearing systems, Cu preferentially partitions into the vapor phase, whereas Zn preferentially fractionates into the hypersaline liquid. The KD values for Cu and Zn obtained in this study correspond well with those obtained from natural fluid inclusions in hydrothermal ore deposits. The results suggest that differential volatility of metals is an important factor affecting the enrichment of certain metals in different hydrothermal ore deposits.

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Mantle xenoliths accompanied in Kurose alkali basalt, especially lherzolite and harzburgite, include small amount of sulfide minerals. Sulfide minerals consist of mainly pentlandite and minor chalcopyrite and monosulfide solid solution (mss). These sulfide minerals occur as inclusions which fill small cracks of silicate minerals. Chemical composition of pentlandite is 17.38-27.91 atom.% Fe and 23.41-34.53 atom.% Ni, respectively. Fe/Ni ratio is 0.50-1.19, suggesting Ni-rich species of pentlandite. This composition of pentlandite suggests that mss crystallizes from the sulfide liquid at about 1000°C, high form pentlandite crystallizes from sulfide liquid at about 850°C, and after subsolidus reaction single phase pentlandite as mentioned above is stable at about 610°C.

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Kobushi skarn deposit is located at northern edge of Kofu Neogene Granitoids, Nagano Prefecture. Intrusion of granodiorite and quartz porphyry brought skarn mineralization on lenticular or irregular blocks of limestone embedded in Mesozoic Kita-Kawahake Formation. Skarns can be grouped into 4 types according to their dominant mineral assemblage such as garnet-, clinopyroxene-, clinopyroxene-, vesuvianite- and amphibole-skarn. There is chemical composion deference of garnet between lower adit and upper adit. Garnet of lower adit is enriched andradite component(93-67 mol%), however, garnet of upper adit is enriched grossular component(79-31 mol%). In addition, this study reports mineral paragenesis, fluid inclusion data and bulk rock chemistry of Kobushi deposit.

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Fe-rich olivine-bearing andesitic dyke occurs in the Shitara area, Aichi, Japan. Petrologic, mineralogic and Raman spectroscopic characteristics of the andesite and Fe-rich olivine were described.

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We determined geochemical features of a hornblende peridotite xenolith within hornblende porphyrite dike from the Tamba belt, Kyoto to reveal deep arc magmatism. The hornblende peridotite is composed of coarse olivine and hornblende with minor amount of clinopyroxene, phlogopite, chromian spinel and orthopyroxene. The olivine and clinopyroxene are magnesian (Mg#, 0.90-0.94 and 0.85-0.89, respectively), and the hornblende, phlogopite and orthopyroxene are less magnesian (Mg# < 0.80). REE and incompatible trace-element patterns of clinopyroxene and hornblende are quite similar to each other. At least two magmas were involved in genesis of this rock. This may indicate multiple supply of a family of magmas in deep part of mantle.

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Although no evidence of volcanism during the Pliocene and Quaternary is known in the Kii Peninsula, it has long been recognized to be several hot springs with discharge temperatures higher than 60°C. Chemical and isotope data were obtained for fluid inclusions trapped in hydrothermal minerals in the peripheral parts of the high-temperature hot springs, and other vein-type ore deposits associated with acidic magmatism of Middle Miocene age. The former inclusions have temperatures of ∼100°C and salinities of about 2 wt % (NaCl equiv.). On the other hand, the latter inclusions are characterized by high temperature fluid (>260°C) with high salinity (>5 wt %). The ³He/⁴He ratios of the former inclusions are generally in agreement with those of the present-day hydrothermal fluids, resulting in no important changes in deep source gases.

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A large ophiolite massif (80 x 40 km) of early Paleozoic age is present in the Ust'-Belaya area in the Koryak Mountains, NE Russia. We have made a joint field research in the summer of 2007. This paper reports on its ultramafic rocks. The ultramafic rocks are divided into three groups: (1) Metaperidotite with cleavable olivine, (2) fertile, granular lherzolite, (3) cumulus dunite-wehrlite-chromitite-troctolite. The metaperidotite contains olivine with abundant tiny magnetite inclusions, chemically heterogeneous (Fo93-87), and associated with sodic tremolite (up to 4 wt. Na2O). The granular lherzolite includes Fo90 olivine, aluminous opx (Al2O3=6 wt.%) and aluminous spinel (Cr#10). The metaperidotite may represent a forearc mantle wedge metasomatized by fluids originated in subduction zone, and the fertile lherzolite and cumulus rocks may represent diapir and magma chamber related to the later island-arc or back-arc basin magmatism.

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We found Grt+Crn+Qtz association from the Red River shear zone.

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Recent geological and petrological investigations of the metamorphic rocks from Vietnam revealed the following new evidences to understand the tectonic evolution of Southeast Asia; 1) findings of ultrahigh-T pelitic granulites, high- to ultrahigh-P mafic metamorphic rocks and high-P/medium-T gneisses from the Kontum Massif, 2) eclogite and high-P granulite from the Song Ma suture zone, and 3) ultrahigh-T aluminous granulite from the Red River zone. These lines of evidence are strongly indicative of the highest-metamorphic conditions in each metamorphic terrane. Estimated P-T conditions and reaction textures from these rocks delineate a characteristic clockwise P-T-t path for each other. A simultaneous collision metamorphism throughout Vietnam should have taken place during the continental collision between Indochina and South China cratons, which leaded to the formation of Trans Vietnam Orogenic Belt.

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The pelitic granulite with migmatitic features is exposed in the central part of the Sør Rondane Mountains. The Grt- and Ky-bearing leucosome locally cuts the pervasive foliations of the pelitic granulite. This pelitic granulite is composed of Grt, Bt, Sil, Ky, Spl, Qtz and Kfs. Equilibrium mineral assemblages are of Grt - Sil - Kfs - Qtz. Sillimanite occurs as inclusions in Grt and matrix, whereas Ky appears in only matrix. Chemical image of Grt indicates the pressure and temperature increase prior to the peak metamorphic conditions. Considering mineral texture and chemical zoning of Grt, the counter-clockwise P-T-t path took place in the pelitic granulite. The Grt- and Ky-bearing leucosome would be produced by the partial melting of the pelitic granulite.

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The Tarkwa gold mines is situated southwestern place in Gahna, belong to the Ashante folded zone. Mines rocks of the Tarwakian group, early Proterozoic age (Age; 2155-2096Ma,2006 annual report). The Tarkwa mining Town is distributed about 50km from the port of Secondi that is face to the Atlantic Ocean. The seashores called the Gold coast and history of development of mines back to 15 century, the Ashante Kingdom. Deposits are recovered from alluvial sources. At Tarkwa gold mines, the mineable reefs consisit of lenses of quarz-pebble conglomerate, matrix consists of sandstones with iron oxides. Sestini(1973) considered the mineralization to be of pareoplacer types, contained ilumenite, rutile, chromite, with additional quartz, carbonates, sericite, chlourite, epidote, tourmaline, zircon, and garnet.

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The properties of hydrothermal clay minerals such as crystallite thickness and its distribution can be related to their formational environments in the hydrothermal systems. In this study chlorite and mica mineral from two 1000m vertical drill holes and hydrothermal ore veins in Toyoha geothermal and mining area were analyzed to calculate crystallite thickness by using the MudMaster computer program(Drits et al., 1996). The averaged particle sizes of chlorite are ranging from 20 to 30nm in thickness. In the lower part of one drill hole, they gradually increase correlating with depth.

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Textural and stable isotopic studies of metabasalts in the Tokoro greenrocks, eastern Hokkaido, Japan, indicate that microbes had a significant role in the alteration of Late Jurassic basaltic glasses. Carbon isotopes (δ¹³C) in calcites from metabasalts also show differences that may relate to microbial activity during alteration before subduction metamorphism. The low (δ¹³C values (ca.-4‰) of calcite were attributed to alteration influenced by Bacteria. Positive δ¹³C values (<1‰) of some samples suggest lithotrophic utilization of CO₂, in which methanogenic Archaea produced CH₄ from H₂ and CO₂.

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This study aims to elucidate the relationship between the granitic magmatism and mineralization by examination of mineral chemistry, fluid inclusion and submicroscopic texture of feldspars for the granitoids in the Uetsu region. The results are: (1) Three kinds of fluid inclusions, liquid-rich, vapor-rich and polyphase inclusions, and the presence of myrmekite indicate that these granitoids have saturated with water except for the Sumikawa granite. (2) Submicroscopic texture of feldspars indicates the duration of hydrothermal water circulation around the Wasada and Iwafune granites was longer than the Nishitagawa and Sumikawa granites, and large ore deposits have developed around the former granites. In addition to petrographic descriptions and observation of fluid inclusion in granites, observation of submicroscopic texture of feldspars gives a good information about water-saturation states and duration of water circulation during the subsolidus stage of the late granitic magmatism, and therefore is a valuable tool to exploration.

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Kuroko ore mine is a special mine developed in Japan,but the organized TEM examination is not done. In this study, observe a transmission electron microscope (TEM) about a Kuroko deposits ore of Sphalerite of Nano-strictures in the Kosaka mine and Syakanai mine. The composition element changes with mineral composition congruently, and 107m has much Cu in comparison with the other parts. Near Yarrow ore increased the GP-Zone in Sphalerite. It became clear that the Nano-organization of the TEM level in the Sphalerite changed with an ore organization and composition. The Nano-organization of Sphalerite reflects generation environment.

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High P2O5(up to 2.1wt %) garnet was reported by Arima and Yamashita(1994,J Mineral Petrol Econ Geol 89(4):166) from rhyolite in Tanzawa mountains. Dendritic crystal surrounding Automorphic garnet crystal is rich in P2O5 and MnO. Apatite is crystallized at outermost of garnet crystal. Melting experiments of Tanzawa rhyolite were conducted under 850-1050°C, 0.5-1.5GPa, 0.0-0.5wt % H2O added. Garnet produced in experiments is hypidiomorphic to allotriomorophic and have quartz inclusions. P2O5 contents of garnet is highest (up to 1.8wt %) in products under 1.5GPa. Variety of garnet Conpositions follows the substitution found in garnet from Tanzawa rhyolite :P+Fe3+=2Si.

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Garnets of the eclogites from the Onodani area in the Besshi district, central Shikoku consist of resorbed spessartine core and overgrowing almandine-rich rim. The spessartine-rich core shows a sector zoning, and it includes such minerals as clinopyroxene, almandine-rich garnet, sodic-calcic amphibole, epidote, albite and quartz. Peak P-T associated with the epidote-blueschist to eclogite facies conditions. The almandine-rich rims of the garnets include clinopyroxene, sodic-calcic amphibole, epidote and quartz. The matrix minerals consisting of garnet, omphacite, epidote, phengite, amphibole, albite and quartz, also representing the peak metamorphic mineral assemblage of the eclogite facies. Omphacites in the matrix are partly or completely altered into omphacite/sodic-augite+hornblende+albite symplectites. And oligoclase and pargasitic amphiboles are in some omphacite/sodic-augite+hornblende symplectite.

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Listwaenite(Hall and Zhao,1995) occured as emerald green altered rock derived from serpentine or pelitic schist in sheared zone of Sambagawa belt along the Median Tectonic Line and Kiyomizu Tectonic zone in Shikoku. Mineral assemblages of listwaenite are dolomite + magnesite + quarts +chromian muscovite + chromian smectite + chromian illite/smectite + Ni-Co-Fe sulfides such as nickeline, gersdorffite ,cobaltite + siegenite and millerite , + native gold. Listwaenite were formed by a metasomatism of low temperature fluid contained CO2 below 200°C.

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A large number of dome-shaped serpentinite seamounts are distributed in the Mariana forearc area. Chrysotile and lizardite are ubiquitous in peridotites throughout the Mariana forearc. Antigorite-bearing rocks, however, were found from Conical and South Chamorro Seamounts which are the farthest seamounts from the trench (at about 90 km west from the trench). Antigorite commonly coexists with acicular diopside and secondary Fe-rich olivine, suggesting high temperature condition during serpentinization. Therefore, it is highly probable that the boundary between shallow chrysotile/lizardite-stable region and deep antigorite-stable region is situated along the subduction boundary just below the area up to 90 km west from the trench (at about 25-30 km depth).

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"Cordierite clusters" up to about 3 cm in diameter abundantly found in Sarugajo type granitic rock (aplitic adamellite) from Takakumayama, Kagoshima, Japan, were examined using optical microscopy, X-ray diffraction, electron probe microanalysis, and X-ray analytical microscopy. The "cordierite clusters" were composed mainly of quartz, alkali feldspar, plagioclase, garnet, cordierite, biotite, muscovite and clinochlore. Compositional map of the "cordierite cluster" disclosed that the microcrystalline clinochlore colored the cluster. An abundance of Fe in the cordierite implies that it was formed pegmatitic stage during cooling of the Takakumayama granite.

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The metamorphic belt in western Mongolia extends over 500 km from the Altai Range along the China-Mongolia border to the Gobi Altai area. Although low- and medium-grade (i.e., greenschist to amphibolite facies) metamorphic rocks have been reported from the Altai Range, few studies on the P-T evolution of the rocks have been done. Here, we report for the first time new petrographic, mineralogic, and thermobarometric data of various metamorphic rocks from several localities along Bodonch River, and discuss regional variations in metamorphic grade. The major units of this region are metasedimentary rocks and granitoids, which are covered by quaternary sediments. The studied area is subdivided in four zones on the basis of lithologies; Zone I: Chl-Ms-Amph zone, Zone II-a: Crn-Ky-Crd zone, Zone II-b: Grt-Ky-Amph zone, and Zone III: staurolite schist with amphibolite zone. All the rocks are fresh and unaltered, and often show obvious foliation defined by aligned micas and amphiboles. The examined samples have the following representative mineral assemblages. Zone I: Chl + Ep + Prg + Olig + Qtz, Ms + Qtz + Bt Zone II-a: Grt + St + Crd + Bt + Ilm + Qtz (sample 05-128), Grt + Ath + Bt + Crd + Qtz (sample 05-126), Chl + Pl + Qtz + Ky (sample 05-124), Crd + Crn + Ky + Rt (sample 05-122), Grt + Bt + Ath + Qtz + Chl + Ilm (sample 445), Zone II-b: Grt + Bt + Ky + Pl + Qtz + Tur (sample 445/1), Grt + Ms + Ky + Bt + Pg + Qtz (sample 446) Zone III: Hbl + Pl + Ilm (sample 443/1), Grt + Ath + Ilm (sample 443/2) Available geothermobarometers were adopted in this study to determine metamorphic temperature conditions of Zones II and III. As the first step, we adopted poikiloblastic garnet and adjacent biotite to calculate metamorphic temperature of Zone II. Application of the method of Ferry and Spear (1978) gave temperature ranges of 510-530 °C (sample 05-128; Zone II-a), 470-510 °C (sample 05-126; Zone II-a), and 520-590 °C (sample 445, Zone II-a). The result is lower than the temperature range of 620-700 °C obtained from hornblende-plagioclase geothermometry of Holland and Blundy (1994) for amphibolite sample 443/1 (Zone III). Such temperature variation is probably due to regional increase of metamorphic grade from Zone II (greenschist facies) to Zone III (amphibolite facies).

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Chatree low-sulfidation epithermal Au-Ag deposit is located in the northern part of Thailand, about 300km north from Bangkok. Deposit is hosted in Loei-Phetchabun Volcanic Belt that crossing Central Thailand. Operation of the mine has been started in 1987 and tonnage of gold is ca. 140t. The mineral resource contains 1.6g/t of Au and 13g/t of Ag. Au occurs as electrum with various sulfide minerals and chlorite. Texture of chlorite-bearing veins colloform to crustiform. The XRD analysis show the clay mineral assemblage of illite and chlorite with some laumontite. Homogenization temperatures and salinities of fluid inclusion in sphalerite are 106-210°Celsius and 0.6-3.3 (NaCl equiv. wt %), respectively. On the other hand, Fluid inclusion in Calcite reveals that ore deposit was formed by relatively low hydrothermal fluid of 100-200°Celsius.

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Gold or electrum from gold mines and placer deposits in Japan were analysed by Energy-Dispersive Spectrometer (EDS) and Electron Microprobe Analyser (EPMA). Gold dusts from placer deposits were analysed by EDS at two conditions: without polishing and with polishing after mounted in glass. Minor and trace elements were analysed by EPMA. Gold and electrum are composed mainly of Au and Ag with subordinate or minor amounts of Hg and Cu. Surface of gold dust is usually higher in Au content than the inner part, probably resulting in leaching of Ag during transportation. There is no critical difference in major and trace elements by region in Japan. Only in Cu-Hg diagram, a weak difference was recognized. Chemical compositions of gold and electrum from both gold mines and placer deposits have not been obtained regionally. Present result may contribute a locality specification of gold and electrum used in cultural heritage.

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The AIST Geological Museum houses approximately 40,000 mineral specimens. Roughly 15,000 specimens have originated from ex-private collections, such as the Okamoto, the Kinoshita, and the Nambu collections. Data on each specimen in those collections have been stored in both the computerized database and the printed catalogues. The data include the name, mineral classification, locality, occurrence or genesis, form, association, mode of acquisition, and photographic image(s).

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We suggest a new geotimer using metamict mineral, especially thorite. It has been experimentally confirmed thorite produces the characteristic granular texture interiorly by heating in metamict state, and similar texture reported in fields for zircon and thorite. Forming this granular texture requires roughly 10 m.y. since crystallization to complete metamictization, in thorite, and this time period is useful for the geotimer to constrain the time interval of thermal events that like intrusion of an old igneous body. On the existing petrology mostly depends isotopic methods for studying these interval of thermal events, on the other hand this geotimer requires only TEM observation and may not affect by various alterations, and that gives a great value of the geotimer.

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The pentlandite enclosed can be formed by phase transition of high-pentlandite which crystallizes primarily by a peritectic reaction between sulfide liquid (magma) and mss at 800 to 900°C in the system Fe-Ni-S.

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The aim of this study is to demonstrate the changes of electrical conductivity associated with dehydration of a microcrystalline quartz aggregate (chalcedony), an analogue material for crustal rocks with grain boundaries containing liquid-like water. This sample contains liquid-like water among grains of a few hundred nanometers and hydroxyl in quartz crystal structure. At the constant temperature of 250, 350 and 450°C, high temperature impedance measurements were continuously performed by about 1 hour intervals, during 6, 6 and 3 days, respectively. At 350°C the electrical conductivity increased from 5 × 10^-5 Sm^-1 to two orders of magnitude higher value. The liquid-like water content, determined by infrared spectroscopy, decreased from 0.3 to 0.1 wt% upon heating, while the hydroxyl content remained mostly unchanged.

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The Si content of silicates were determinded by micro-wave digestion method. The solutions of silicates were prepared by closed-vessel digestion using mixed-acid attacks. The solutions were measured by inductively coupled plasma-atomic emission spectrometry (ICP-AES). SiO2 reagent was simultaneously digested with unknown samples to determine the recovery yield of Si. The results were corrected by the recovery yield. Recovery yields of Si were approximately above 90%. The corrected results of geological reference samples were in good agreement with the recommended values.

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Some vanadium minerals, palenzonaite, nabiasite, tokyoite, and two Mn-V-hydrous oxides are found from the Yamato mine, Kagoshima Prefecture, Japan. The mine is famous for the occurrence of such vanadium minerals as haradaite, goldmanite, and roscoelite. Palenzonaite occurs as wine-red aggregates up to 1.5mm wide composed of minute anhedral grains in manganese silicate or as crusts on braunite. Nabiasite occurs as veinlets cutting braunite. Tokyoite is found as dark-red, platy grains up to 0.3mm in fissures of manganese silicate. Two Mn-V-hydrous oxides occur as the secondary products of reddish brown grains in fracture of quartz and rhodonite including haradaite. Although the chemical compositions of both materials are corresponding to ansermetite (MnV2O6•4H2O) and fianelite (Mn2V2O7•2H2O), respectively, the X-ray diffraction patterns do not coincide with those of ansermetite and fianelite.

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Mn-Ca-V-Al garnet was found in metamorphosed manganese ore deposit of the Tanohata mine, Iwate Prefecture, Japan. The chemical analyses indicate maximum mole of the ideal Mn-V garnet in the present material reaches 57%. It is predicted that the crystal system of the present garnet is not cubic because distinct anisotropic nature is observed under the microscope.Nagashimalite is also found in qurtz crystal in association with Mn-Ca-V-Al garnet.

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