| 摘要: |
| 古湖泊砂砾堤研究表明,24kaB.P., 兹格塘错、错鄂分别存在10m、30m(高出现代湖面)的高湖面, 湖泊面积分别可达272km2、220km2, 是现代湖泊的1.42、3.12倍。与此相比, 9.0—6.0kaB.P.湖面略低；在兹格塘错, 古湖泊高出现代湖面8m, 面积约为246km2, 比现代大56km2；在错鄂,古湖面高出现代12m, 面积约为138km2。基于Kutzbach水能联合方程,利用逐
次逼近法取得有关参数, 重建的各流域上述各时期的降水量分别可达(400±20)mm/a (兹格塘错24kaB.P.)、(535±20)mm/a (错鄂24kaB.P.)、(370±20)mm/a (兹格塘错9.0—6.0kaB.P.)、(470±20)mm/a (错鄂9.0—6.0kaB.P.)。
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| 关键词: 青藏高原湖泊, 湖泊砂砾堤, 24kaB.P.高湖面, 9.0—6.0kaB.P.高湖面 |
| DOI：10.11693/hyhz200303007007 |
| 分类号: |
| 基金项目:国家重点基础研究发展规划项目,G1998040800号 |
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| PRELIMINARY STUDY OF LAKE EVOLUTION AND PRECIPITATION OF ZIGETANGCO AND COE BASINS, CENTRAL QINGHAI-XIZANG PLATEAU, SINCE 24kaB.P. |
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JIA Yu-Lian,WANG Su-Min,WU Yan-Hong,LI Shi-Jie,JIANG Xue-Zhong
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1.Department of Urban and Resources, Nanjing University;2.Nanjing Institute of Geography and Limnology,The Chinese Academy of Sciences
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| Abstract: |
| Evidence from gravel-sand bars around lakes shows that the lakes in the central Qinghai-Xizang Plateau have at least four high-level stages since 24kaB.P.. 24kaB.P. and 9.0—6.0kaB.P. high lake level stands are discovered in ZigeTangco and Coe catchment basins. 15.5kaB.P. and 2.2kaB.P. high lake levels are discovered in Zige Tangco and Coe basins, respectively. During the periods of around 24kaB.P. and 9.0—6.0kaB.P., in the Zige tangco catchment, the palaeolakes occupied 272km2 and 246km2, respectively, with lake levels being 10m and 8m higher than the present; for the same periods, the palaeolakes in the Coe catchment, which is at the southeast of Zigetangco catchment, had areas of 220km2 and 138km2, respectively, being 30m and 12m higher than the present. Using Kutzbach′s equation of energy balance to compute land evaporation and water surface evaporation with step-after-step approaching method to obtain the parameters, and modeling the combined hydrological and energy balance of
Zigetangco and Coe basins, the following estimates of precipitation were yielded: (400±20)mm/a at 24kaB.P. and (370±20)mm/a at 9.0—6.0kaB.P., in Zigetangco catchment, and (535±20)mm/a at 24kaB.P. and (470±20)mm/a at 9.0—6.0kaB.P., in Coe catchment, respectively.
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| Key words: Lakes on Qinghai-Xizang Plateau, Gravel and sand bar, 24kaB.P. high lake level stand, 9.0—6.0kaB.P.high lake level stand |
