Stable carbon and oxygen isotopic dispersions of individual foraminifera: new proxy to estimate the sea environmental condition precisely

2015 Fiscal Year Final Research Report

• Project/Area Number: 26550016
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Environmental dynamic analysis
• Research Institution: Ibaraki National College of Technology
• Principal Investigator: ISHIMURA Toyoho 茨城工業高等専門学校, 物質工学科, 准教授 (80422012)
• Co-Investigator(Kenkyū-buntansha): IKEHARA Ken 国立研究開発法人・産業技術総合研究所, 地質情報研究部門, 総括研究主幹 (40356423) ; HASEGAWA Shiro 東北大学, 学術資源研究公開センター, 協力研究員 (90142918)
• Project Period (FY): 2014-04-01 – 2016-03-31
• Keywords: 安定同位体比 / 底生有孔虫 / 分散 / 底層環境 / 再堆積 / 微量分析 / 環境指標 / Uvigerina属

Outline of Final Research Achievements

We have investigated the stable isotopic dispersions of individual benthic foraminifera to utilize them as new sea environmental proxy. The second aim of this study is to reutilize the archived sediment samples already taken from all over the world. As the results, we found that the stable carbon and oxygen isotopic compositions of Uvigerina akitaensis show the most reliable isotopic composition (low dispersion, close to isotopic equilibrium values) among several sampling sites. In addition, we found that Nonionellina labradorica, Bolivina spissa, Islandiella norcrossi, and Globocassidulina sp. also have reliable isotopic compositions. Besides, we found that we can utilize the isotopic dispersions of benthic foraminifera to evaluate the redeposition of sediment.

Free Research Field

安定同位体微古生物学