Carbon Dioxide Controls: Pleistocene Carbonate Saturation Fluctuations in the West-Equatorial Pacific

我们已经为西赤道太平洋的现代沉积物生成了一个定量有效的溶解指数，该指数与碳酸盐饱和度值有关。我们希望将这一指数应用于在onong - java高原斜坡上的一系列长岩心，以重建该地区近450年来深水的饱和历史。时间尺度将由氧同位素地层学与Imbrie等人（1984）标准的拟合提供。溶蚀的绝对速率将通过比较溶斜层上方和下方岩心的同步瞬时积累速率得出，并与溶蚀指数核对。校正后的饱和度曲线与底栖有孔虫的同位素组成数据相结合，可以确定深水中可能的二氧化碳分压，并为重建晚更新世的碳化学和循环提供有用的约束。我们的重点是布伦什时间中后期的对比，以及极端状态（冰期-间冰期）和极端变化率（冰川化-消冰川化）之间的对比。

We have generated a quantitatively valid dissolution index for modern sediments in the west-equatorial Pacific, which is tied to carbonate saturation values. We wish to apply this index to a series of long cores, taken across the lysocline on the slope of Ontong-Java Plateau, in order to reconstruct the saturation history of deep waters in this region, for the last 450 kyr. The time scale will be provided by a fit of oxygen isotope stratigraphy to the Imbrie et al. (1984) standard. Absolute rates of dissolution will be derived from comparison of synchronous instantaneous accumulation rates of cores from above and below the lysocline, checked against dissolution indices. In conjunction with data on the isotopic compositions of benthic foraminifera, the calibrated saturation curves will allow determination of probable pCO2 of deep waters, and provide useful contraints on the reconstruction of the late Pleistocene carbon chemistry and circulation. Our focus is on the contrast between middle and late Brunhes time, and on that between the extreme states (glacial-interglacial) and the extreme rates of change (glacierization-deglaciation).