东昆仑阿拉克湖地区第四纪地层时代厘定及环境变迁

根据沉积分析和ESR、OSL1、4C测年数据,对阿拉克湖地区第四纪地层进行了详细的成因划分和时间约束,为第四纪以来高原隆升重大事件及其引起的环境演变提供了重要的时代依据;根据沉积特征和孢粉植物演替对第四纪的环境变迁过程进行了探讨:早更新世湖积地层中出现具亚寒带气候特征的针叶林植物群和中更新世冰碛物覆于早更新世地层之上是研究区第四纪环境演变的重要转折标志;第四纪盆山耦合关系非常明显,山系隆升与沉积盆地具有由北向南迁移的规律。

Age determinations of the Quaternary strata and environmental changes in the Alag Lake area,East Kunlun

The detailed genetic classification and age determinations of the Quaternary strata in the Alag Lake area,East Kunlun are made on the basis of sediment analysis and ESR,OSL and ~ 14C dating.The results of research in this study have provided important basis for the further approaches to the major tectonic events of the Qinghai-Xizang Plateau uplifting and resultant environmental changes since the Quaternary.The Quaternary environmental changes are discussed in the light of sediments and sporopollens in the Quaternary strata.The occurrence of the subfrigid coniferous forests in the early Pleistocene lacustrine strata and overlying of the middle Pleistocene glacial deposits upon the early Pleistocene lacustrine strata may be interpreted as important marks indicating environmental changes in the Quaternary,when the basinrange coupling is apparent,and mountainrange uplifting and sedimentary basins tend to be migrated from north to south.