西昆仑苏巴什东部侏罗系杨叶组孢粉化石的发现及其沉积环境分析

Discoveryand Sedimentary Environment of Sporopollen Fossils at Jurassic Yangye Formation in East Subashi,West Kunlun

西昆仑苏巴什东部的侏罗系杨叶组地层,位于康西瓦-木孜塔格构造混杂岩带北侧的昆南增生杂岩带之上对。对该地层研究对探讨西昆仑地区侏罗系沉积环境和构造演化具有十分重要的意义。通过对其孢粉的研究,表明了该套地层形成于中侏罗世早期,并且指示出其古气候为温暖潮湿环境;结合区域地质背景,认为该地层形成于中侏罗世早期,且为一套浅湖-滨湖相沉积环境。

In the east Subashi of West Qunlun, the Yangye Formation is occurred in the accre- tionary wedge of the South Qunlun belt, which located at the north side of the Kangxiwa-Muzi- tange tectonic complex. The study of this stratigraphic unit is important for understanding the Jurassic paleogeography and tectonic evolution in West Qunlun. Sporo-pollen study shows that this stratigraphic unit was deposited during the early stage of Middle Jurassic epoch and was formed in warm and humid environment. After carrying out the regional geological research, pollen study and geochemistry study, the results suggest that the Yangye Formation was deposited during the early stage of Mid-Jurassic epoch and was formed in a shallow lake and shore lake environment.