地理学报 ›› 2011, Vol. 66 ›› Issue (1): 123-130.doi: 10.11821/xb201101012

• 地貌与第四纪 • 上一篇    下一篇

云南小中甸盆地湖相沉积记录的最近5 次Heinrich事件

明庆忠, 苏怀, 史正涛, 董铭, 张文翔   

  1. 云南师范大学旅游与地理科学学院,昆明650092
  • 收稿日期:2010-08-29 修回日期:2010-11-12 出版日期:2011-01-25 发布日期:2011-03-11
  • 作者简介:明庆忠(1963-), 男, 湖北黄冈市人, 教授, 中国地理学会会员(S110002334M), 主要从事地理环境及旅游规划研究。E-mail: mingqingzhong01@163.com
  • 基金资助:

    国家自然科学基金(U0933604; 40872118); 云南省中青年学术带头人培养基金; 云南省科技发展计划2009 年重点项目; 教育部科学技术研究重点项目(207102); 云南省科技计划项目(2007D199M;2010CD043)

Last Five Heinrich Events Revealed by Lacustrine Sediments from Xiaozhongdian Basin in Yunnan Province

MING Qingzhong, SU Huai, SHI Zhengtao, DONG Ming, ZHANGWenxiang   

  1. College of Tourism and Geography Sciences, Yunnan Normal University, Kunming 650092, China
  • Received:2010-08-29 Revised:2010-11-12 Online:2011-01-25 Published:2011-03-11
  • Supported by:

    National Natural Science Foundation of China, No.U0933604; No.40872118; Young and Middle-aged Academic Leader Training Foundation of Yunnan Province; 2009 Key Program of Yunnan Science and Technology Development Funds; Key Project of the Ministry of Education of China, No.207102; Science and Technology Planning Project of Yunnan Province, No.2007D199M; No.2010CD043

摘要: 通过对小中甸盆地厚15.3 m的湖相沉积进行系统的粒度、孢粉和地球化学元素分析,结合 14C年代测定,发现小中甸盆地在最近40 ka 以来经历了5 次湖泊收缩事件,其形成年代可以同北大西洋的Heinrich 事件H0-H4逐一对比,指示西南季风不仅在其水汽源区,而且在其控制的内陆腹地对最近40ka 以来的Heinrich 事件都存在敏感的响应。与在水汽源区所表现不同的是,Heinrich 事件在内陆地区主要表现为干旱。通过与西南季风水汽源地之一的阿拉伯海深海沉积记录和格陵兰冰芯记录进一步对比发现,小中甸盆地仅对千年尺度的Heinrich 冷事件信号敏感而对D/O (Dansgaard-Oescher) 暖事件缺乏明显记录,这与阿拉伯海的响应模式有较大差异。分析周边环流形势认为,冰期青藏高原对西南季风“抽吸”作用的减弱是造成小中甸盆地D/O暖信号记录不明显的重要原因。

关键词: 小中甸, 西南季风, Heinrich事件

Abstract: Xiaozhongdian Basin is located in the southeastern margin of the Qinghai-Tibet Plateau which is completely controlled by southwest monsoonal circulation. A thick continental lacustrine sedimentary sequence is preserved due to late Cenozoic fault depression and offers a unique opportunity to study the variability of the southwest monsoonal circulation in detail. Based on the analytical results of grain size, spore-pollen and geochemical elements and 14C datings from a 15.3-m-long lacustrine stratum, five lake dry and shrink events during the last 40 ka, which might be correlated to Heinrich events H0-H4 discovered in North Atlantic region, have been found in Xiaozhongdian Basin, suggesting that Heinrich events for the last 40 ka are strongly imprinted not only in moisture source area of southwest monsoonal circulation, but also in inland area controlled by this circulation. The Heinrich events footprint became drier in inland area, differently from that in moisture source area. However, the signals of the D/O (Dansgaard-Oescher) warm events, which are also clearly recorded in Greenland ice cores and Arabian Sea sediment cores, are ambiguous in Xiaozhongdian Basin. According to the general circulation patterns, we believe that the effect attenuation of the Qinghai-Tibet Plateau on “Pumping Action”of southwest monsoonal circulation system during the glacial periods should be responsible for this phenomenon.

Key words: Xiaozhongdian Basin, southwest monsoonal circulation, Heinrich events