西菲律宾海GX149柱状样沉积物磁学性质及其环境意义

发布时间：2018-05-05 15:51

  本文选题：西菲律宾海 + 磁学特征　； 参考：《地学前缘》2017年03期

【摘要】：对取自西菲律宾海西部的GX149柱状样沉积物进行详细的环境磁学研究,揭示其蕴含的环境意义和物源信息。岩石磁学结果表明,GX149柱状样沉积物中携磁矿物以低矫顽力磁铁矿为主;反映磁性颗粒粒径的King图与Day图显示沉积物中磁性矿物以准单畴(PSD)为主。剖面上磁学参数变化明显,以磁性矿物粒径参数(χARM/χ)作为替代指标反演古气候变化结果显示:冷期沉积物中磁性矿物含量相对更高,粒径更粗,高矫顽力矿物含量增加;而暖期沉积物中磁性矿物含量相对较低,粒径更细,高矫顽力矿物含量降低。干燥、寒冷、风大的冷期气候下,东亚季风携带的粉尘输入增加导致沉积物中高矫顽力矿物含量增多;而温暖湿润的暖期,沉积物中风成粉尘输入减少,高矫顽力矿物含量降低。GX149柱状样沉积物与西菲律宾海其他区域以及南海沉积物相似的磁学特征,相同的冰期-间冰期旋回趋势说明沉积物磁学特征对气候变化的响应在东亚地区具有共性。
[Abstract]:A detailed environmental magnetic study of GX149 columnar sediments from the west of the western Philippine Sea was carried out to reveal the environmental significance and provenance information contained therein. The results of rock magnetism show that the magnetic carrying minerals in the columnar sediments of GX149 are mainly low coercivity magnetite, and the King and Day diagrams reflecting the particle size of magnetic particles show that the magnetic minerals in the sediments are quasi-single-domain PSDs. The magnetic parameters changed obviously in the section. The paleoclimate change was inversed by the magnetic mineral particle size parameter (蠂 ARM/ 蠂). The results showed that the content of magnetic minerals was higher, the diameter of magnetic minerals was larger, and the content of high coercivity mineral was higher in cold period sediment. However, the content of magnetic minerals in warm sediments is relatively low, the particle size is smaller, and the content of high coercivity minerals is lower. In the dry, cold and windy climate, the dust input from the East Asian monsoon increases the content of high coercivity minerals in the sediments, while in the warm and humid warm period, the dust input from the sediment is reduced. Reduction of high coercivity mineral content. GX149 columnar sediments have similar magnetic characteristics to other areas of the West Philippine Sea and the South China Sea. The same trend of glacial to interglacial cycles indicates that the magnetic response of sediments to climate change is common in East Asia.
【作者单位】： 国土资源部海底矿产资源重点实验室;中国地质调查局广州海洋地质调查局;中国地质调查局;广东省有色地质勘查院;
【基金】：国土资源部海底矿产资源重点实验室开放基金课题(KLMMR-2014-A-12) 国家自然科学基金项目(41306042,41272384) 中国地质调查局地质调查项目(GZH201300502,GZH201500202)
【分类号】：P736.21
，

本文编号：1848299