印度洋赤道海岭钙质软泥天然热释光变化特征与冰川旋回关系

赤道东经90°海岭的MD81349活塞柱状岩芯包含300ka以来类型丰富的环境变化信息.作者应用天然热释光技术对岩芯的全样沉积物和浮游有孔虫壳体进行分析测定,首次得到与氧同位素分期呈良好对应关系的天然热释光变化曲线.实验数据表明,天然热释光的高强度区和低强度分别能够指示间冰期与冰期.初步分析显示,天然热释光强度变化在一定程度上与碳酸钙含量无关;在远洋型抱球虫软泥物质组成基本一致的情况下,其变化特征极有可能受到不同气候条件下形成的有孔虫壳体的晶体类型、晶格缺陷形式、杂质元素的控制.

Thermoluminescence change of carbonate ooze from Ninetyeast Eidge of Indian Ocean near equator and its relation to glacial cycles

Piston core MD81349 from the Ninetyeast Ridge of the Indian Ocean near the equator records more information of environmental changes during the past 300 ka. The thermoluminescence (TL) (technique) has been used to analyze bulk samples and foraminiferal shells of the core. The TL fluctuations that can well correlate with the oxygen isotope curve was obtained for the first time. Experimental data suggest that the high and low NTL intensities may indicate the interglacial and glacial stages, respectively. Analysis shows that the NTL intensities is not related to the content of calcium carbonate; in the case of the essentially consistent composition of pelagic globigerina oozes, however, the variation is most likely to be controlled by the crystal types, lattice defect forms and impurity ions in the crystal lattice of (foraminiferal) shells formed under different climatic conditions.