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柴达木盆地尕海湖沉积物粒度特征及其古气候意义

陈碧珊 潘安定 张元芳

陈碧珊, 潘安定, 张元芳. 柴达木盆地尕海湖沉积物粒度特征及其古气候意义[J]. 海洋地质与第四纪地质, 2010, 30(2): 111-119. doi: 10.3724/SP.J.1140.2010.02111
引用本文: 陈碧珊, 潘安定, 张元芳. 柴达木盆地尕海湖沉积物粒度特征及其古气候意义[J]. 海洋地质与第四纪地质, 2010, 30(2): 111-119. doi: 10.3724/SP.J.1140.2010.02111
CHEN Bishan, PAN Anding, ZHANG Yuanfang. GRAIN-SIZE CHARACTERISTICS AND THEIR ENVIRONMENTAL SIGNIFICANCE OF GAHAI LAKE SEDIMENTS IN QAIDAM BASIN[J]. Marine Geology & Quaternary Geology, 2010, 30(2): 111-119. doi: 10.3724/SP.J.1140.2010.02111
Citation: CHEN Bishan, PAN Anding, ZHANG Yuanfang. GRAIN-SIZE CHARACTERISTICS AND THEIR ENVIRONMENTAL SIGNIFICANCE OF GAHAI LAKE SEDIMENTS IN QAIDAM BASIN[J]. Marine Geology & Quaternary Geology, 2010, 30(2): 111-119. doi: 10.3724/SP.J.1140.2010.02111

柴达木盆地尕海湖沉积物粒度特征及其古气候意义


doi: 10.3724/SP.J.1140.2010.02111
详细信息
    作者简介:

    陈碧珊(1982-),女,硕士生,主要从事环境演变与自然灾害研究,E-mail:chenbishan2008@126.com

  • 基金项目:

    国家自然科学基金项目(40671187)

  • 中图分类号: P532

GRAIN-SIZE CHARACTERISTICS AND THEIR ENVIRONMENTAL SIGNIFICANCE OF GAHAI LAKE SEDIMENTS IN QAIDAM BASIN

More Information
  • 摘要: 以尕海湖DG02钻孔沉积物为研究对象,利用高分辨率的粒度数据,结合岩性、孢粉特征,分析其粒度特征及近11 000 aBP来的气候环境变化。研究发现,尕海湖沉积物记录了该区域湖泊水体逐渐上升又逐渐减少的过程,气候环境变化大致分为4个阶段:(1)冰消期晚期(11 324~10 290 aBP)气候干旱,湖泊水位下降,面积收缩,水动力较强,沉积颗粒较粗;(2)早全新世(10 290~8 850 aBP),气候转向湿润,湖泊水位上升,为浅水至深水的过渡阶段,颗粒由粗变细;(3)中全新世(8 850~4 400 aBP),气候更加湿润,湖水水位达到最高,面积扩大,水动力达到最弱,沉积颗粒最细;(4)晚全新世(4 400~200 aBP),气候变干,湖泊强烈收缩,湖面下降,水动力达到最强,沉积颗粒最粗。尕海湖DG02钻孔沉积物粒度所记录的区域气候干湿变化及一些重要的干湿事件与国内外研究显示出较好的一致性。
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出版历程
  • 收稿日期:  2009-07-12
  • 修回日期:  2009-09-25

柴达木盆地尕海湖沉积物粒度特征及其古气候意义

doi: 10.3724/SP.J.1140.2010.02111
    作者简介:

    陈碧珊(1982-),女,硕士生,主要从事环境演变与自然灾害研究,E-mail:chenbishan2008@126.com

基金项目:

国家自然科学基金项目(40671187)

  • 中图分类号: P532

摘要: 以尕海湖DG02钻孔沉积物为研究对象,利用高分辨率的粒度数据,结合岩性、孢粉特征,分析其粒度特征及近11 000 aBP来的气候环境变化。研究发现,尕海湖沉积物记录了该区域湖泊水体逐渐上升又逐渐减少的过程,气候环境变化大致分为4个阶段:(1)冰消期晚期(11 324~10 290 aBP)气候干旱,湖泊水位下降,面积收缩,水动力较强,沉积颗粒较粗;(2)早全新世(10 290~8 850 aBP),气候转向湿润,湖泊水位上升,为浅水至深水的过渡阶段,颗粒由粗变细;(3)中全新世(8 850~4 400 aBP),气候更加湿润,湖水水位达到最高,面积扩大,水动力达到最弱,沉积颗粒最细;(4)晚全新世(4 400~200 aBP),气候变干,湖泊强烈收缩,湖面下降,水动力达到最强,沉积颗粒最粗。尕海湖DG02钻孔沉积物粒度所记录的区域气候干湿变化及一些重要的干湿事件与国内外研究显示出较好的一致性。

English Abstract

参考文献 (39)

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