A comparative study of boron isotopes and trace elements of the marine foraminifers during the last glacial maximum and Holocene

作者：Ni YunYan^*

来源：Science China Earth Sciences, 2010, 53(1): 91-100.

DOI：10.1007/s11430-009-0179-8

• foraminifers
• boron isotope
• trace element
• last glacial maximum
• atmospheric PCO(2)

Boron isotopic compositions in marine planktonic foraminifers can record changes in seawater pH and hence provide a new tool to reconstruct the changes of paleo-atmospheric PCO(2). Here a comparative study was done on boron isotopes and trace element abundances of planktonic foraminifers, Globigerinoides sacculifer and Globigerinoides ruber from three tropical ODP sites, Site 806B, Site 664C and Site 999A. It is demonstrated here that G. ruber is a better species to be used for downcore boron isotope analyses on glacial-interglacial scales, particularly since G. sacculifer is prone to dissolution causing unexpectedly light boron isotopes during glacial times. It has been shown that the trace elements composition of foraminifers (i.e., Mg/Ca, U/Ca, B/Ca, and Li/Ca) can reflect the variations of seawater temperature and/or [CO(3)(2-)]. However, all of these systems are highly species de-pendent and affected by other vital effects, and it is therefore important to perform necessary calibrations when applying them to the downcore analyses.

• 出版日期2010-1
• 单位中国石油天然气股份有限公司勘探开发研究院