近13万年来南沙沉积物中的剩磁记录

杨小强; 周文娟; 高芳蕾; 李华梅

近13万年来南沙沉积物中的剩磁记录

1 中山大学地球科学系地球环境与地球资源研究中心, 广州 510275;
2 中国科学院广州地球化学研究所, 广州 510640

基金项目:

中国科学院创新项目(KZCX3-SW220)

国家自然科学基金(40104002)

详细信息

作者简介:
杨小强(1972-),男,副教授,博士,从事第四纪环境与环境磁学方面的研究,E-mail:ee93@zsu.edu.cn

中图分类号: P539.3
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出版历程
- 收稿日期: 2005-07-10
- 修回日期: 2005-10-07

REMANENCE MAGNETIC RECORDS FROM RECENT 130 000 YEARS IN SEDIMENTS OF NANSHA AREA, SOUTH CHINA SEA

1 Department of Earth Sciences, Zhongshan University, Guangzhou 510275, China;
2 Guangzhou Institude of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China

摘要

摘要: 对长355 cm的南沙NS93-5钻孔连续取古地磁样品281块,进行沉积物磁性特征的研究。详细的岩石磁学结果表明,沉积物中以低矫顽磁力的磁性矿物为主,剩磁携带者主要是磁铁矿类矿物,但同时存在少量赤铁矿和磁赤铁矿等。钻孔191~206、232~248和292~308 cm记录的剩磁磁倾角出现较小的负值,根据氧同位素地层学和¹⁴C测年、火山灰层年龄,计算其对应的沉积年龄分别为65.87~68.7、73.4~80.8和108.4~113.6 kaBP。其中108.4~113.6 kaBP的剩磁异常可能是布莱克(Blake)事件在南沙沉积物中的记录。
- 磁性矿物 /
- 剩磁磁倾角 /
- Blake事件 /
- 南沙
Abstract: 281 samples, collected from the NS93-5 drilling core located in the Nansha area of South China Sea, were used to study magnetic characteristics of sediments in the Sea. Detailed rock magnetic results show that the magnetic minerals of sediments were dominated by ferrimagnetic minerals such as magnetite, but the small contribution of hematite and maghematite also existed. The sediments recorded three negative values of inclination in 191~206, 232~248 and 292~308 cm. The corresponding age of these negative values are 65.87~68.7, 73.4~80.8 and 108.4~113.6 kaBP according to stratigraphy of oxygen isotope, ¹⁴C and the age of volcano. The negative value during 108.4~113.6 kaBP may be the record of Blake event in the sediments of Nansha area.
- magnetic minerals /
- remanence magnetic inclination /
- Blake event

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参考文献(22)

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