2013 Fiscal Year Final Research Report

Development of new reliable environmental proxies for reconstructing bottom-water conditions

Research Project

Project/Area Number	24651017
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Single-year Grants
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)
Project Period (FY)	2012-04-01 – 2014-03-31
Keywords	安定同位体比 / 底層水 / 有孔虫 / 微量分析 / 環境指標 / 生物源炭酸塩 / 古環境解析 / 海洋環境
Research Abstract	We analyzed the isotopic composition of individual benthic foraminifera of multiple species by using a customized high-precision analytical system, and found that the magnitude of the isotopic disequilibrium between benthic foraminiferal shell and the surrounding bottom seawater in different species is correlated with inter-individual isotopic variations. As a result, we can choose suitable species as bottom-water proxies by using the inter-individual isotopic variations. Our findings will allow the use of isotope data for benthic foraminifera as more reliable proxies for reconstructing past bottom-water conditions.