The chemical compositions of biotite grains have been determined for early Paleozoic plutonic rocks from the Sør Rondane Mountains, East Antarctica. The plutonic rocks are divided into three groups of the type-I granitoids, type-II granitoids and the Mefjell Plutonic Complex. Two types of biotite are found in the groups: pale yellow to dark green biotite in the type-I granitoids and brown to dark brown biotite in the type-II granitoids and the Mefjell Plutonic Complex. Mineral chemically, biotites from the type-I granitoids have higher SiO₂ contents, F contents, and X_Mg values with lower TiO₂ and Cl contents relative to biotites from the type-II granitoids. In the type-II granitoids and the Mefjell Plutonic Complex, biotite strongly enriched in FeO has lower F contents. Biotites in the type-II granitoids and the Mefjell Plutonic Complex have much higher log(f_H2O)/(f_HF) than those from the type-I granitoids. The fluorine content in biotite from the type-I granitoids is similar to that from partial melting A-type granites in Lachlan Fold Belt of eastern Australia; and those from the type-II granitoids and the Mefjell Plutonic Complex are comparable to fractionated aluminous A-type granites from the Lachlan Fold Belt, and the Ambalavayal aluminous Atype granites of South India. Lower fluorine contents in biotite from the type-II granitoids and the Mefjell Plutonic Complex may be mainly controlled by late-magmatic fluid-rock interaction processes associated with melt and may not be indicative of original magma contents. Higher fluorine contents in biotite and whole-rock from the type-I granitoids may reflect fluorine-enriched magmatic source. Our results in biotites from the type-I granitoids as well as geochemistry support the models, which fluorine-rich A-type granites may be derived from partial molten crustal igneous rocks of tonalitic to granodiorite composition.

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Ishimaki and Tahara limestones occur as exotic blocks juxtaposed in the Mesozoic (Jurassic) accretionary complex of Southern Chichibu Terrane in eastern Aichi Prefecture, central Japan. They are supposed to be of the seamount-type limestone, since they have no terrigenous materials and are intimately associated with greenstones. REE (rare earth elements) and Sr isotopic studies for the limestones have been made in order to know their geochemical characteristics, ages and origins. Their ⁸⁷Sr/⁸⁶Sr ratios, when referred to the seawater ⁸⁷Sr/⁸⁶Sr curve and relevant geological data, suggest that Ishimaki and Tahara limestones are the late Permian and the Carboniferous to the Early Permian, respectively. Two greenstone fragments found inside the Ishimaki limestone block and one greenstone sample associated with Tahara limestone block, resemble the Hawaiian alkali basalt in their REE and Y patterns. This is supporting the idea that the limestone blocks may be parts of reef limestones on ancient volcanic seamounts. All the limestone samples, except three unusual Tahara ones, show seawater REE and Y signatures in their chondrite-normalized patterns. Their REE/Ca ratios, however, are 10²-10⁴ times as high as those ratios of modern biogenic carbonates like corals and the seawater. Accordingly, seawater REE and Y were incorporated into the limestones, when originally biogenic carbonates transformed into inorganic calcite and its secondary growths occurred in diagenesis in contact with sufficient seawater. This view is favored by the reported REE partition experiment between calcite overgrowths and seawater solution. The seawater Ce anomaly as a function of water depth in the modern ocean is a key to infer the water depth of the REE and Y incorporation. The Ce anomalies given by log(Ce/Ce^∗) for about a half of Ishimaki samples and most of Tahara ones are between -0.5 and -0.2, which are compatible with the shallow water origin. Another half of Ishimaki samples, however, have log(Ce/Ce^∗) values between -0.7 and -1.0, suggesting moderately deep waters (ca. 500-1000 m deep or more). This may reflect such a situation that water depths of REE incorporation into the seamount-type limestones are generally greater than the depositional water depths of original biogenic carbonates because of the fate of limestone-capped volcanic seamounts decided by the oceanic plate motion.

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The concentrations of major elements and rare earth elements (REE) of the stream waters from the Rokko granite area, Japan, were analyzed to examine the relationship between the degree of weathering and chemistry of the waters. The clay minerals in the related soils from the watershed areas were also examined. It was found that the relative proportion of kaolinite to total clay minerals is a good measure for the degree of weathering of the area. The Ca concentrations of the stream waters are rather high in comparison with other cations such as Na, K and Mg, and are well correlated with HCO₃^-. These facts indicate that the Ca concentrations in the stream waters are largely controlled by dissolution of calcite that occurs as disseminated crystals in granites. The Ca/Na molar ratio in the waters decreases with increasing kaolinite/clay ratio in the related soils. The high Ca waters tend to occur in the fresh or weakly weathered areas, which is attributed to abundant calcite in these granites. By contrast, in the strongly weathered areas, where calcite had already been consumed via previous weathering processes, low Ca waters occur. The REE abundances, especially light REE, of the stream waters tend to be high in the strongly weathered watershed areas, and low in the fresh or weakly weathered watershed areas. This is attributed to either enhanced REE leaching from rocks in strongly weathered watershed areas due to larger solid surface areas or increased weathering of accessory minerals such as apatite. Interestingly, the magnitude of negative Ce anomalies appears to be inversely related to the degree of weathering. We suggest that the magnitude of Ce anomalies in those waters is largely controlled by mechanical filtration of CeO₂ during infiltration in micro-cracks or pores rather than by Eh-pH conditions.

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Two distinct groups of mine waters are found at Libiola. They are red acid waters (pH 2.4-2.8) and blue neutral waters (pH 7.0-7.5), based on the color of the precipitating solid phases. Few occurrences have characteristics intermediate between those of red waters and blue waters. The irreversible mass exchanges taking place during interaction of meteoric waters with mine-waste materials and addition of local groundwaters to acid mine waters were simulated by means of the software package EQ3/6. Results of these simulations were compared with the analytical data of mine waters through activity plots, showing the fields of stability of dominant sulfate, hydroxide, and carbonate minerals. The activity plots and the bimodal distribution of pH in mine waters indicate that the main process governing the chemistry of the mine waters of Libiola is variable interaction of meteoric waters with mine-spoil materials. Mixing between local groundwaters and acid mine waters plays a minor role, if any.

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Distributions, seasonal variation, flux and contamination source of pesticides and nonylphenol were examined during the period from April 2001 to January 2002 at 5 sites (Namitakiji, Tokumasa-Kami, Izumi, Ochiai and Hinotsume) in Kurose River water, Higashi-Hiroshima, Japan. Water samples were collected monthly and subjected to solid phase extraction followed by GC-MS analysis. Nineteen pesticide compounds were detected and isoprothiolane (37 ng/l), fenitrothion (35) and iprodione (34) showed the highest mean concentrations (as 5 site averages), while pencycuron (5), diazinon (6), tolclofos methyl (7) and dithiopyr (8) were the compounds of lowest mean concentrations. Nonylphenol, which is a degradation product of a nonylphenolpolyethoxylates that are used in a wide range of industrial and household products, had an average concentration of 305 ng/l. At each of the five sites, its concentration was greater than individual pesticides. The concentration levels of pesticides and nonylphenol were highest at Izumi (the downtown site of Higashi Hiroshima) and were lowest at Namitakiji and Tokumasa-Kami (upstream sites). Concentrations and fluxes of both compounds tended to be higher during spring to summer and low during fall to winter at most of the sites. The total pesticides concentration was poorly correlated with nonylphenol concentration. A statistical analysis of water quality data suggested that their main sources appear to be different such as agricultural activity for pesticides and waste water discharge for nonylphenol.

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The Zhantang andesites, which erupted in the Late Cretaceous Huichang Basin of SE China interior, were associated with the Late Mesozoic lithospheric extension and basaltic underplating. They are high-Na (6.59-8.46 wt% Na₂O), high-Al trondhjemitic rocks with high Sr and Ba, low Y and HREE, and high Sr/Y and La/Yb ratios, similar to modern adakites. However, they are much higher in Na₂O but lower in CaO than adakites. Their εNd(T) values of -2.3 to -3.8 and initial ⁸⁷Sr/⁸⁶Sr ratios of 0.707 to 0.708 are also significantly different from those of adakites with MORB-like isotopic compositions. These chemical and isotopic features, along with the tectonic setting, suggest that they were not produced by partial melting of subducting slab. The Zhantang adakite-like magmas may be derived from underplated basaltic lower crust, but require a compositionally peculiar basaltic protolith to account for their extremely high-Na and low-Ca feature. They are compositionally comparable to the experimentally produced partial melts of alkali-rich basalt. We therefore interpret them as the products of melting of an alkali-rich basaltic rock.

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Mid infrared throughput using 5 μm apertures was investigated using micro-FTIR spectrometers with conventional light sources at two laboratories and the synchrotron radiation infrared (SR-IR) light source at SPring-8. With both the light sources micro-FTIR microscopy can analyze the fundamental O-H vibration in andesitic glass with 1 weight % H₂O through 5 μm apertures. Spectra obtained at SPring-8 show better relative standard deviations due to the brighter and more highly collimated nature of SR-IR compared to conventional light sources. The spectra with 100 and 1000 scans at SPring-8 have similar relative standard deviations to those with 1000 and 10200 scans, respectively, at laboratories. The successful analysis with 5 μm apertures using both light sources shows the potential for an improvement in the spatial resolution of micro-FTIR analyses.

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A sediment trap experiment and stable carbon and nitrogen isotope analysis of sinking organic particles have been performed in the northeast Japan Sea from August 1998 to October 1999 in order to confirm the relationship between seasonal variability of phytoplankton production and the isotope composition of sinking particles. The sediment trap deployed at 1090 m has successfully recovered samples recording organic particles sinking for a year round. Increases of POC and total mass fluxes suggested that blooming occur twice a year in late autumn and early summer in this region. It was shown that the seasonal variation of δ¹³C and δ¹⁵N of sinking particles could be explained by the general pattern controlling isotope ratios of phytoplankton so that appearance of isotope fractionation on photosynthesis and nitrate uptake might play a most important role to change δ¹³C and δ¹⁵N of phytoplankton in tightly linked with nutrient supply and production rate in the mixed layer. The δ¹³C and δ¹⁵N of the surface sediment were significantly heavier than those of sinking particles and showed a consistent trend of vertical isotopic change with the results reported in previous works. Compiled such vertical trend we addressed that carbon and nitrogen isotopic discrimination between sinking particles and the surface sediment might be qualified by the bottom depth due to isotope discrimination in sinking process but further modification can occur by regional factors such as import of allochthonous substances. Finally we stress about the implication of such factor to apply isotopic proxies to paleoceanographic research.

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We have studied the REE distribution in shallow marine continental platform carbonates belonging to two late Neoproterozoic basins of India. Their REE abundance patterns normalized by chondrite display well defined W-type tetrad effect. Based on chondrite-normalized Gd/Ho, La/Nd ratios, the REE abundance patterns have been classified into three groups. (Y/Ho) and (Y/Dy) concentration ratios reflect a combined effect of Y fractionation relative to neighboring trivalent REEs during carbonate precipitation from seawater and influence of continental contributions with chondritic ratios. Negative Ce anomalies recorded in Krol and Bilara carbonates resembles the Ce anomaly reported from shallow marine waters. However, absence of Ce anomaly and distinct positive anomalies in some of our carbonate samples reflect post-depositional redox condition related to Ce mobilization and preferential enrichment during early diagenesis. Variations in the REE abundance patterns may be attributed to contamination with terrigenous particulates having shale like REE abundances and post-depositional early diagenetic processes.

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Staining is a useful laboratory tool for distinguishing specific carbonate minerals from a mixture of carbonates. Feigl's and Meigen's solutions are commonly used to distinguish aragonite from other carbonates. Feigl's solution stains the aragonite surface black and Meigen's stains purple, whereas the coexisting calcite remains nochang in color with either solutions. Both methods were applied to an authigenically precipitated carbonate chimney and a recrystallized metamorphic marble. Meigen's solution was favorable to stain fine and euhedral aragonites, but not effective for recrystallized aragonites. Feigl's solution was applicable to identify both types of aragonites. As a sample that demonstrates application of the Meigen's solution, isotopic analyses were carried out on aragonite and calcite separated from the seepage carbonate chimney collected from the Conical seamount of the Mariana forearc.

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