With the aim of better understanding geochemistry of coal, 416 borehole samples of coal, one parting, two floor and two roof mudstones were collected from 9 minable coal seams in 24 boreholes drilled during exploration in the Huainan Coalfield, Anhui, China, and 47 elements were determined by various analytical techniques. The depositional environment, abundance, distribution, and affinity of elements were investigated. Results shown that the boron concentration in the coals indicates a brackish water depositional environment in this study region and marine influence decreased from coal seam 1 to 13-1. Some potentially toxic elements (e.g., Se, Cd) are higher than their averages for Chinese coals. The roof, floor and parting samples have higher contents of some elements than do the coal seams. The minerals in the coals from the Huainan Coalfield were found to consist mainly of clays, carbonates and sulfides. The elements can be classified into two groups based on their stratigraphic distribution from coal seam 1 to 13-1, and the characteristics of each group are discussed in detail. The elements may be classified into four groups (i.e., Group 1 to 4) according to their correlation coefficients with ash yield. The elements in Group 1, Group 2, and Group 3 are strongly correlated with ash yield, while the elements in Group 4 have weak or negative correlation coefficients.

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Chemical and stable isotopic compositions (δD, δ¹⁸O, and δ³⁴S) of non-volcanic hot spring waters around the Miocene Kofu granitic complex surrounding the Kofu basin in the South Fossa Magna region of central Honshu, Japan, were analyzed in order to investigate water-rock interactions and to determine the origin and sulfur isotopic characteristics of their trace amounts of SO₄^2- ion. All water samples from the granitic rocks were classified as Na-Alkalinity (Alk) type, whereas water samples from the volcanic rocks were classified as Na-Alk, Na-SO₄, Na-SO₄·Cl·Alk, and Ca-SO₄ types. The water in the samples originated from meteoric water, and the average recharge altitude of the samples ranged from 947 m to 1397 m based on the altitude effect of δ¹⁸O. The Na-Alk type waters from the granitic rocks were likely formed by the montmorillonization of plagioclase, cation exchange reaction of Na-montmorillonite, and calcite precipitation. Trace amounts of SO₄^2- ion of this type of water were derived from the oxidation of sulfide such as pyrite in granitic rocks or the roof sedimentary rocks of the Shimanto group, where H⁺ caused by the sulfide oxidation was consumed in the process of plagioclase weathering. SO₄^2- ion content in the Na-Alk type water from the granitic rocks reflected the δ³⁴S values of granitic and sedimentary rocks of the Shimanto group. Water samples from the ilmenite series area have negative values ranging from -15.1 to -4.6‰, whereas waters from the magnetite series area have positive δ³⁴S values ranging from +1.7 to +8.0‰. The hot spring water quality of the Na-Alk, Na-SO₄, Na-SO₄·Cl·Alk, and Ca-SO₄ types from the volcanic rocks area were estimated to be controlled by anhydrite dissolution, plagioclase weathering, cation exchange reaction of Na-montmorillonite, and precipitation of calcite during the fluid flow and mixing process. Different concentrations of SO₄^2- ions determined for these waters have a wide range of δ³⁴S values ranging from -4.1 to +13.6‰, which is likely attributed to the dissolution of ³⁴S-rich and ³⁴S-poor anhydrite. The ³⁴S-rich SO₄^2- ions were interpreted to be derived from sulfate in sulfuric acid, which arose from the disproportionation reaction of volcanic sulfur dioxide, whereas the ³⁴S-poor SO₄^2- ions were derived from the oxidation of ascending hydrogen sulfide in shallow ground waters during the active stage of past volcanism.

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Two active hydrothermal fields, Jade and Hakurei fields have been discovered within the Izena Hole, a rectangular 6 km × 3 km shape depression located in the middle Okinawa Trough back arc basin. In both fields, intense hydrothermal activity is represented by venting of high-temperature fluid (>300°C) and occurrence of sulfide/sulfate ore deposits. We collected hydrothermal fluids during dive expeditions of ROV Hyper Dolphin conducted in 2003, 2010 and 2011, in order to analyze both elemental and gas species. The geochemistry of high temperature hydrothermal fluids collected from the Jade and Hakurei fields is very similar to each other with exceptions in minor gas composition. Little temporal variation was observed in geochemistry of the high-temperature hydrothermal fluid of the Jade field over two decades, since a previous study carried out in 1989. These results suggest that these fluids are derived from a common fluid reservoir where fluid chemistry is basically controlled by fluid-mineral equilibria and gas species are dominantly contributed from the same magma. Venting of low temperature fluid (about 104°C) was discovered in the distal part of the Jade field, which was named as the Biwako vent. Chemical composition of the Biwako vent fluid was distinctive from that of the high temperature fluid in the proximal part of the Jade field, and could not be explained by simple dilution or cooling. This intra-field chemical diversity could be caused by phase separation and segregation during fluid upwelling, based on relationships in concentrations of Cl and major cations. On the other hand, the chemical diversity recognized in minor gas composition between the Jade and Hakurei fields is in accordance with results from previous plume survey. Difference in concentrations of minor gases such as H₂ is attributed to contribution from thermal degradation of organic matter in the sediment, during fluid upwelling.

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Some trees from tropical areas lack visually detectable and consistent annual growth rings. As such, we have measured the radial variation of cellulose oxygen isotopes in trees that grow in seasonally dry forests of Northern Laos to explore the possibility if this method can be used for the identification of annual rings. One disk from a 7-year-old Styrax tonkinensis (S. tonkinensis) in plantation and two cores from two Ficus semicordata var. semicordata (F. semicordata) in forests were examined. High-resolution cellulose oxygen isotopes of S. tonkinensis and F. semicordata show clear cycles with amplitudes of 5‰ and 9‰, respectively. To further test if the oxygen isotope cycles that we observed are annual or not, a tree ring cellulose oxygen isotope model is employed. Input data of the model are relative humidity and modeled precipitation δ¹⁸O. The modeling results independently support our detection of oxygen isotope annual cycles. Therefore, we conclude that tree ring cellulose oxygen isotopes have great potential to identify annual rings in tropical trees, which typically lack distinct annual rings in the context of seasonal climate.

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The Dajing deposit is a large-scale vein-type polymetallic Sn deposit in the southern Great Xing'an Range of Northeast China. This study presents new geochronological and geochemical data for subvolcanic rocks associated with the Dajing deposit and discusses the petrogenesis and tectonic setting of these rocks. The subvolcanic rocks associated with the Dajing deposit are felsites, porphyritic andesites, and porphyritic dacites. Laser-ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS) U-Pb Zircon dating undertaken during this study indicates that the porphyritic dacite was intruded during the late Permian (265.9 ± 5.4 Ma), whereas both the felsite and the porphyritic andesite were intruded during the Middle Jurassic (168.4 ± 5.0 and 175.5 ± 5.6 Ma, respectively). All of these subvolcanic rocks are of the high-K calc-alkaline series, with high A/CNK (=(Al₂O₃)/(CaO + Na₂O + K₂O)) molecular ratios (>1), and are LREE-enriched relative to the HREEs. The felsite is characterized by relatively high Rb, U, Nd, Zr, and Hf, and relatively low Eu, Ba, Sr, P, and Ti concentrations, and is geochemically similar to highly fractionated I-type granites. In comparison, the porphyritic andesite is characterized by relatively high Rb and K and relatively low Ba concentrations, and is geochemically similar to unfractionated I-type granites. The porphyritic dacite is enriched in Rb, Zr, and Hf, is depleted in Ba, Sr, P, and Ti, and is geochemically similar to A₂-type granites. The regional geological setting and geochemistry of these subvolcanic rocks indicate that both the felsite and porphyritic andesite formed during post-collisional extension within the Xingmeng Orogenic Belt. This extension was a far-field effect of the closure of the Mongol-Okhotsk Ocean and associated lithospheric delamination during the Middle Jurassic. In comparison, the porphyritic dacite was associated with post-collisional slab break-off.

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The hydrogen and oxygen isotopic characteristics of precipitation in coastal areas of Japan were explained on the basis of a long period (23 years) observation of hydrogen and oxygen isotopic ratios (δD and δ¹⁸O) of precipitation collected monthly at Akita as well as a short period (1 or 2 years) observation at other localities. Coastal precipitation is characterized by a high d-value (=δD-8δ¹⁸O) in winter and a low d-value in spring to fall, and the d-value of annual mean precipitation depends on the mixing ratio of these two types and is generally higher (15-18) on the Japan Sea side and lower (11-12) on the Pacific Ocean side. The average values of δD and δ¹⁸O of monthly precipitation in winter are in ranges of -50 to -30‰ in δD and -9.0 to -6.5‰ in δ¹⁸O from northern Honshu to southern Kyushu, and the values in spring to fall are in the ranges of -55 to -45‰ in δD and -8.0 to -7.0‰ in δ¹⁸O. These variations seem to be mainly due to differences in sea surface temperature of the Japan Sea or Pacific Ocean where source vapor of precipitation is supplied. The values of δD and δ¹⁸O of annual mean precipitation are in the ranges of -55 to -40‰ and -8.6 to -6.7‰, respectively, between northern Honshu to southern Kyushu. The slopes of the δD and δ¹⁸O relationship are almost the same in winter and spring to fall and are close to 8 of Craig's meteoric line. This suggests that δD and δ¹⁸O in these two seasons are controlled by the same isotopic fractionation processes in source vapor supply except for the kinetic effect and in cloud forming processes. Therefore, if the kinetic effect is eliminated, δD and δ¹⁸O show similar seasonal variation patterns.

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In Antarctica, the geochemical properties of meltwater and pondwater are very sensitive to global warming. Therefore, understanding the geochemical properties of the meltwater and pondwater is crucial to evaluating global climate change. This study was performed to examine the chemical and isotopic compositions of the meltwater and pondwater at the Barton and Weaver Peninsulas of King George Island, Antarctica, to understand their spatial variation and to evaluate factors controlling the surface water chemistry. The meltwater, pondwater and seawater were sampled at 50 sites of the Barton and Weaver Peninsulas during the period from 23 December 2010 to 5 January 2011. The chemical compositions of the meltwater and pondwater were mainly influenced by sea salt. Additionally, the influence of water-rock interaction was observed in some meltwater and pondwater. The LREE/HREE ratios of some of the pondwater in the Barton Peninsula showed a decreasing trend by influence of water-rock interaction. The influences of sea salt and water-rock interaction were more dominant at the Barton Peninsula than the Weaver Peninsula. The δ¹⁸O and δD of the meltwater and pondwater showed a wide range. Little evaporation losses were observed at the Barton Peninsula but evaporation losses did not occurred at the Weaver Peninsula.

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We cultivated Isopora palifera clone colonies at six different temperatures for testing the utility of its skeletal δ¹⁸O as a paleotemperature proxy. Specimens cultivated at higher temperatures exhibited lower calcification rates, especially at 31.0°C, than those cultured at lower temperatures. The skeletal δ¹⁸O of the specimens cultured at 21.1-29.5°C correlated strongly with water temperature, and δ¹⁸O-temperature sensitivity was -0.15‰ °C^-1. When we removed the thermal factor from the skeletal δ¹⁸O and δ¹³C trends at 21.1-29.5°C by subtracting the estimated equilibrium values of inorganic aragonite from the analyzed δ¹⁸O and δ¹³C values, we found that the calcification rate variation has little influence on the isotopic compositions of the specimens examined. Thus, the skeletal δ¹⁸O of I. palifera corals without severe bleaching can be a good temperature proxy at temperatures below ∼30°C.

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We determined the stable nitrogen isotopic composition (δ¹⁵N) of amino acids in bone collagen from samples of three archaeological herbivores (cattle, sheep, and goats), collected from the Tell Ain el-Kerkh Neolithic site in Syria. Bulk collagen δ¹⁵N values exhibited significant differences between the three species (by up to 3.2‰), and were strongly correlated with those of glycine (R² = 0.87), the most abundant amino acid in bone collagen. On the other hand, the δ¹⁵N values of two other minor amino acids (glutamic acid and phenylalanine) in the different samples were within narrow ranges (0.9‰ and 0.5‰, respectively), and exhibited either weak or no correlation with those of bulk collagen. The trophic position estimated by the δ¹⁵N values of glutamic acid and phenylalanine (2.0 ± 0.1) is consistent with that of herbivores. These results suggest that the δ¹⁵N values of bulk bone collagen may vary among herbivores, partly on account of their differing amino acid compositions, whereas the trophic position of different herbivores is faithfully preserved in the δ¹⁵N values of glutamic acid and phenylalanine.

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