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通过对东北太平洋胡安·德富卡隆起西翼沉积柱样中的碳酸盐含量和浮游有孔虫氧同位素测试以及浮游有孔虫丰度、溶解指数和粗组分的统计,发现在晚第四纪约65 ka以来碳酸盐含量变化幅度大(0 4%~77 2%),相差非常悬殊,但其变化未呈现出冰期时溶解作用减弱、间冰期时溶解作用强烈这样明显的旋回性。粗组分分析结果显示,地层中有明显的浊流沉积发育。另外,碳酸盐含量和浮游有孔虫丰度分析结果揭露了研究区的 CCD在3 500 m左右。研究认为,在约65 ka来水深浅于3 500 m的区域碳酸盐含量的无规律性变化应与浊流沉积影响有直接的关系,而水深深于3 500 m的区域碳酸盐含量主要受控于深海碳酸盐的溶解作用。
Based on the carbonate content and the planktonic foraminiferal oxygen isotope test and the abundance of planktonic foraminifera, dissolution index and coarse fraction in the sediments of the western wing of the Juan de Fucarca uplift in the northeast Pacific Ocean, it was found that at night Since the Quaternary was about 65 ka, the carbonate content varied greatly (from 0 4% to 77 2%), but the difference was not obvious. However, the change did not show the dissolution weakening during the glacial period and strong obvious dissolution during the interglacial period Sex. Crude composition analysis results show that there are obvious turbidity flow deposits in the strata. In addition, the carbonate content and abundance of planktonic foraminifera revealed that the CCD of the study area was about 3 500 m. The study suggests that the irregular change of carbonate content at a water depth of about 65 ka at a depth of about 3,500 m should be directly related to the influence of turbidity flow deposition while the carbonate content at a depth of 3,500 m is mainly Controlled by the dissolution of deep-sea carbonate.