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对比分析了太平洋(Site 806)、大西洋(Site 664)和加勒比海地区(Site 999)末次冰期最盛期和全新世钻孔顶部不同尺寸大小的浮游有孔虫Globigerinoides sacculifer(500～600μm和300～355μm)和Globi-gerinoides ruber(300～355μm和250～300μm)的硼同位素组分变化,发现个体相对较小的有孔虫样品由于受到样品量以及样品前处理过程的影响,其硼同位素在末次冰期最盛期出现异常,浮游有孔虫硼同位素分析,尤其是冰期-间冰期时间尺度上的硼同位素分析,适合用个体相对较大的有孔虫。末次冰期最盛期太平洋和加勒比海地区溶解作用可能加强,其G.sacculifer的硼同位素偏低,但G.ruber的硼同位素不受溶解作用的影响,能够反映末次冰期海水pH值的变化。三个钻孔末次冰期最盛期G.ruber的硼同位素比全新世的硼同位素平均高(1.3±1.2)‰(2s.e.),与理论预测值1.6‰一致。
The comparison of the glacial-borne foraminifera Globigerinoides sacculifer (500 ~ 600μm and 300 ~ 355μm) at the top of the borehole at the peak of the Last Glacial and the Holocene at Site 806, Site 664 and Site 999, ) And Globi-gerinoides ruber (300 ~ 355μm and 250 ~ 300μm). It was found that the boron isotopic composition of the relatively smaller foraminiferal samples in the last glacial period was affected by the sample amount and the pretreatment process. Abnormal in the peak period, the analysis of boron isotopes of planktonic foraminifera, especially the boron isotope analysis on the time scale of glacial-interglacial period, is suitable for the relatively large foraminifera. The dissolution of G.sacculifer may be lower in the Pacific Ocean and the Caribbean at the peak of the last ice age, but the boron isotopes of G.ruber are not affected by the dissolution and reflect the changes of seawater pH during the last ice age. The boron isotopes of G.ruber from the three boreholes during the last ice age were higher than those of Holocene (1.3 ± 1.2) ‰ (2s.e.) on average, consistent with the theoretical prediction of 1.6 ‰.