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To evaluate whether 87Sr/86Sr ratio of a bone reflects 87Sr/86Sr ratio of the birth- and growth-places, two bone samples, together with the geological samples in their birth- and growth-places, were measured for 87Sr/86Sr ratios by TIMS. The samples used are a boar collected at Asuke, Toyota City, Aichi prefecture, and a black bass collected from Lake Biwa. The 87Sr/86Sr ratio of the boar bone was 0.71001±0.00002, while those of stream sediments in the Asuke area was around 0.710. The 87Sr/86Sr ratio of the black bass bone was 0.71215±0.00002, while those of surface water at the southern basin in Lake Biwa was 0.71233±0.00002. The similar 87Sr/86Sr ratios between bone and its provenance geology indicates that the 87Sr/86Sr ratio of bone reflects the isotopic ratios of the birth- and growth-places.

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We have developed the analytical method of lithium (Li) isotopic ratio using twice-steps column separation protocol and the third generation MC-ICP-MS (NEPTUNE, Thermo Sci.) that was installed at Kochi Core Center. The high sensitivity of the NEPTUNE MC-ICP-MS enabled high precision analyses (±0.3‰, 2SD) with sub-nanomol Li level.

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Large variations of chlorine isotopic composition (δ 37Cl=-5~+8‰ SMOC) have been reported for bulk chondrites, MORB and other rocks. Rcently, Sharp et al (2007) claimed that reported high TIMS δ 37Cl values were too high compared to those obtained by the Gas-Source MS (IRMS) and possibly artificial. We report here additional TIMS results for chondrites and compared them with those of IRMS.

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ICP-MS is one of indispensable tools for trace metal analysis. The history of ICP-MS has been pursuit of higher sensitivity and elimination of interferences. The collision/reaction cell technology becomes the major system of ICP-MS in order to overcome the interferences. This paper represents what are differences between collision cell and reaction cell, and kinetic energy discrimination and dynamic bandpass tuning.

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Low molecular weight dicarboxylic acids are abundant in atmospheric aerosols in continental, marine and polar reions. They are water-soluble and thus can act as cloud condensation nuclei, playing an important role in radiative forcing of the Earth and also in water cycle. Here, we studied dicarboxylic acids in the marine aerosols (n=32) from the Pacific (34°N-14°S, 140°E-150°W) for their stable carbon isotopic ratios using a capillary GC/isotope ratios mass spectrometer (GC/irMS) after dibutyl ester derivatization. We found a significant diversity of δ13C values for C2-C9 saturated and some unsaturated diacids as follows: oxalic acid (av. +10.3 ‰), malonic (-7.3 ‰), succinic (-17.6 ‰), glutaric (?23.0 ‰), adipic (?16.0 ‰), pimelic (- 22.1 ‰), suberic (-16.3 ‰), azelaic (-22.4 ‰), fumaric (-17.2 ‰), and phthalic (-22.2 ‰) acids. Heaviest δ13C values were obtained for C2 and C3 diacids especially over the tropical Pacific, suggesting an isotopic enrichment possibly caused by photochemical processes.

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Massive corals have been widely used as proxies for past changes in sea surface temperature (SST) of the tropical and subtropical oceans because the oxygen isotopic and strontium/calcium (Sr/Ca) ratios of their aragonitic skeletons are believed to vary as a function of the temperature of the ambient seawater. However, recent microanalytical studies using secondary ion mass spectrometry (SIMS) have revealed large chemical heterogeneities for Sr/Ca and oxygen isotopic ratios in coral skeleton, which cannot be explained by temperature variation (e.g. Meibom et al., 2004, Rollin-Bard, et al., 2003)

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The Songnen saline land (SSL) is located in the semi-arid region of the northeastern part of China where lies in the pathway of Asian dust transport from Mongolian deserts. It was proposed that the dust loading from SSL can increase the dust deposition in the downwind areas such as Northeastern China, Korea and Japan. The carbon and oxygen isotope analyses of soil carbonate from SSL might be useful for examining the hypothesis about recently increased dust deposition. The carbon and oxygen isotope variations of soil carbonate from SSL will be discussed.

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