首页 | 本学科首页   官方微博 | 高级检索  
     检索      

东亚夏季风变迁的灵敏的指标:黄土碳酸盐的~(87)Sr/~(86)Sr比值
引用本文:朱洪兵,杨杰东,陈骏.东亚夏季风变迁的灵敏的指标:黄土碳酸盐的~(87)Sr/~(86)Sr比值[J].南京大学学报(自然科学版),1998(6).
作者姓名:朱洪兵  杨杰东  陈骏
作者单位:南京大学地球科学系!210093(朱洪兵,陈骏),南京大学现代分析中心!南京大学成矿作用国家重点实验室,210093,南京(杨杰东)
基金项目:国家杰出青年科学基金!49725307,国家教育部博士点基金
摘    要:对130ka以来陕西洛川黑木沟剖面的黄土和古土壤碳酸盐中银同位素进行的系统测定显示.在末次间冰期期间87Sr/86Sr平均值为0.71136,末次冰期期间87Sr/86Sr平均值为0.71079.古土壤碳酸盐的87Sr/86Sr比值明显高于黄土碳酸盐的87Sr/86Sr比值.导致这种差别的主要原因是化学风化强度的变化.研究表明,黄土和古土壤碳酸盐87Sr/86Sr比值的变化是现出一个由本次间冰期到未次冰期的约10万年的周期,在这个周期变化的总趋势之上又覆盖了一种波动周期约在2.5ka~2.7ka的高频波动变化.它与小冰期年龄(LittleIceAge)大致吻合.黄土碳酸盐87Sr/86Sr比值的这种高振幅和周期的变化.表明它可能是一种反映东亚夏季风变化的高灵敏度的替代指标.

关 键 词:锶同位素  黄土碳酸盐  季风  黄土高原

VARIATIONS IN~(87)Sr/~(86)Sr RATIOS OF CARBONATES OF CHINESE LOESS-PALEOSOL:A PROXY INDEX OF THE EAST ASIAN SUMMER MONSOON
Zhu Hongbing, Yang Jiedong, Chen Jun.VARIATIONS IN~(87)Sr/~(86)Sr RATIOS OF CARBONATES OF CHINESE LOESS-PALEOSOL:A PROXY INDEX OF THE EAST ASIAN SUMMER MONSOON[J].Journal of Nanjing University: Nat Sci Ed,1998(6).
Authors:Zhu Hongbing  Yang Jiedong  Chen Jun
Abstract:The investigation of Sr isotopes for loess and paleosol carbonates of the Himugou section near Luochuan of Xi'an in China shows that87Sr/86Sr ratios of paleosols are higher than those of loesses and87Sr/86Srratios of the last interglacial period are higher than those of the last glacial period. The Variation in chemicalweathering strength is the main cause leading to the change in87Sr/86Sr ratios of paleosol and loess carbonates.THe study strongly suggests that a glacial-interglacial cycle of-100 Ka exits in87Sr/86Sr record of loess-paleosol carbonates and the high frequency flucturations of-2.7 Ka cycle are imprinted in the general changetrend of the glacial-interglacial cycle of-100 Ka, indicating that Sr isotope of loess-paleosol carbonates maybe an excellent proxy of the East Asian summer monsoon.
Keywords:Sr isotope  loess  Luochuan  monsoon
本文献已被 CNKI 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号