新疆玛纳斯河兴农湖沉积物特征反映的古环境探讨

Analysis on the Sedimentary Environment of Xingnong Lake Section of Manas River

大量研究表明沉积物的粒度和粘土矿物可以作为研究环境演变的载体。玛纳斯河兴农湖剖面位于新疆维吾尔自治区克拉玛依市附近的一个农场内。本文分析了该剖面的粒度变化特点和粘土矿物的类型与含量变化。研究表明,兴农湖剖面以湖相沉积为主,位于古玛纳斯湖的边缘,是古玛纳斯湖的一部分。粘土矿物主要由伊利石、蒙皂石、高岭石和绿泥石组成。根据粒度和粘土矿物分析,将兴农湖沉积环境演变划分为9个阶段。

A lot of research shows that the clay minerals and grain size of the sediments can be served as signs of the climate changes. The Manas River is the largest stream in the north margin of Tianshan Mountains. The Xingnong Lake section lies in a farm which is near Kelamai city in Xinjiang Uygur Autonomous Region. The clay mineral and grain size characteristics of Xingnong lake swamp sediments were measured. The result showed that the Xingnong Lake section can be contributed to lacustrine deposition and this region once was the part of the ancient Manas Lake. The main types of clay minerals are illite, smectite, kaolinite and chlorite. Based on the grain size and clay minerals types and contents, nine climatic stages were recognized.