Host: Abstracts of Annual Meeting of the Geochemical Society of Japan
Name : Abstracts of Annual Meeting of the Geochemical Society of Japan
Number : 69
Date : September 05, 2022 - September 16, 2022
Pages 163-
Mo and W are group 6 elements and have similar chemical properties. However, the two elements behave in a different way in the hydrosphere. Recently, progression of the analytical technology allows us to measure the isotope ratios for heavy elements, such as transition metals. The concentrations and isotope ratios of Mo and W are potential tracers of hydrothermal activity and anthropogenic contamination. However, there are still few data particularly for W. This study is aimed to provide with simultaneous data of dissolved Mo and W throughout the hydrosphere. Water samples from the North Pacific Ocean, the Indian Ocean, the East China Sea, the Sea of Japan, Osaka Bay, Yodo River and Uji River were analyzed. We measured the concentration of Mo and W, δ98/95Mo, and δ186/184W. We found that the concentrations and isotope ratios of W are uniform in the open ocean with a similar manner to Mo. The W data of Osaka Bay are significantly different from the oceanic values, and the W data of Yodo River are significantly different from the Uji River values. Also in the Japan and East China Seas, the data of W show slight difference. We propose that anthropogenic W has significant contributions in these areas.
