| 引用本文: | 陈诗越,王苏民,沈吉.青藏高原中部错鄂湖晚新生代以来的沉积环境演变及其构造隆升意义.湖泊科学,2003,15(1):21-27. DOI:10.18307/2003.0103 |
| CHEN Shiyue,WANG Sumin,SHEN Ji.Variations of Sedimentary Environments during Late Cenozoic of Co Ngoin, Central Tibetan Plateau and Its Tectonic Uplift Implications. J. Lake Sci.2003,15(1):21-27. DOI:10.18307/2003.0103 |
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| 摘要: |
| 错鄂湖200m深井岩芯古地磁测年表明错鄂湖形成于约2.8Ma年前.沉积岩性组合粒度特征和磁化率变化揭示了约3次大的沉积环境变化过程反映了至少2次剧烈的青藏高原隆升过程同时孢粉组合也揭示了构造隆升导致的植被组合的变化.初步研究认为大的湖泊沉积环境变化主要是在青藏高原不断隆升的背景上进行的.2.8-2.5Ma和0.8Ma以来的沉积环境演化主要受构造运动的控制而2.5-0.8Ma环境演化过程更多的受到冰期-间冰期旋回气候变化的影响. |
| 关键词: 青藏高原 错鄂湖 粒度特征 沉积环境 |
| DOI：10.18307/2003.0103 |
| 分类号: |
| 基金项目:国家重点基础研究发展规划G1998040810资助项目. |
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| Variations of Sedimentary Environments during Late Cenozoic of Co Ngoin, Central Tibetan Plateau and Its Tectonic Uplift Implications |
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CHEN Shiyue1,2, WANG Sumin1, SHEN Ji1
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1.Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, P. R. China;2.The Graduate School of The Chinese Academy of Sciences, Beijing, 100039, P. R. China
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| Abstract: |
| The paleomagnitism dating of the core Co Ngoin, Qinghai-Tibetan Plateau, a 200-m-depth core taken from Co Ngoin, indicates that the lake emerges at 2.8Ma BP. Lithological property, grain size and magnetic susceptibility (sus) reveal three major significant environmental variations and at least two tectonic uplifts during the last 2.8Ma. Accordingly, pollen associations open out the vegetation changes controlled by the tectonic uplift. Studies show that the major environmental changes were largely controlled by stepwise uplift of the Qinghai-Tibetan Plateau, and those numerous small changes overlapped on the large tectonic background are mainly controlled by the global climatic changes of glacial and interglacial cycles in Quaternary. The thickness of the strata above the B/M boundary is thinner, which might be resulted from the glacial cover to lead the shortage in stratigraphic thickness. |
| Key words: Qinghai-Tibetan Plateau Co Ngoin grain size environmental changes |
