Geochemical cycles in sea environments around the Japanese Archipelago from distributions of multi-radionuclides

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K00518
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Environmental dynamic analysis
• Research Institution: Kanazawa University
• Principal Investigator: Inoue Mutsuo 金沢大学, 環日本海域環境研究センター, 准教授 (60283090)
• Co-Investigator(Kenkyū-buntansha): 山本 政儀 金沢大学, 理工研究域, 特任教授 (10121295) ; 長尾 誠也 金沢大学, 環日本海域環境研究センター, 教授 (20343014) ; 浜島 靖典 金沢大学, 環日本海域環境研究センター, 准教授 (60172970)
• Co-Investigator(Renkei-kenkyūsha): FUJIMOTO Ken 国立研究開発法人 水産研究・教育機構, 中央水産研究所, 研究員 (20371841)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 放射性核種 / ガンマ線計測 / 日本海 / 物質循環

Outline of Final Research Achievements

Soluble and reactive radionuclides (Ra-226, Ra-228, Cs-134, Cs-137, Th-228, and Th-234) in seawater have been used as powerful tracers to investigate geochemical cycles in marine environments. By employing low-background gamma-spectrometry, we conduct fine-resolution observations of spatial and seasonal variations of these radionuclides in the Sea of Japan (and the neighboring East China Sea and Okhotsk Sea), and assess the circulation patterns of water masses and particles. Furthermore, the migration of Ra-228 readily explained the expanding pattern of the 2011 Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident-derived radiocesium around the Japanese Archipelago.

Free Research Field

海洋化学