演題概要

オーラルセッション

第3日　5月13日（水）　10:05～10:25　C会場（1101/02）

3C-O12-1005　　PDF

浮遊性有孔虫のホウ素同位体分析を通じた海洋炭素循環研究

(¹神戸大院人・ ²海洋機構・ ³東大大海研・ ⁴金沢大院自然・ ⁵高知大院教育)
^o窪田薫^1,2・ 横山祐典^2,3・ 石川剛志²・ 佐川拓也⁴・ 池原実⁵・ 山崎俊嗣³

Boron isotope proxy of biogenic calcium carbonate is widely used in paleoclimatology to reconstruct seawater pH and carbon dioxide concentration in the atmosphere. But boron isotope measurement of foraminifera shell has been one of the most difficult analysis in geochemistry, due to small amount of boron in calcite shell of foraminifera, strict requirement in precision in use of paleoclimatology, and its susceptibleness to contamination sourced from laboratory environment. In the presentation I will show results of boron isotope analysis of the shells of two species of surface-dwelling foraminifera from the same marine sediment core collected from the western equatorial Pacific, which is to investigate marine carbon cycle in glacial-interglacial timescales.