塔里木盆地库车坳陷东部早-中侏罗统沉积物源分析
Provenance analysis of the Early-Middle Jurassic deposits in eastern Kuqa depression in the Tarim Basin, Xinjiang
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摘要: 根据岩心观察、重矿物特征、单井岩性剖面及相关指数的综合研究,认为早-中侏罗世期间,库车坳陷东部主要接受南天山物源区提供的碎屑物,而塔北隆起提供的碎屑物则比较有限。根据下-中侏罗统碎屑岩中重矿物和碎屑组分的差异,进一步将各期物源区在东西方向上划分成4个物源补给亚区。此外,从下侏罗统阿合组、阳霞组到中侏罗统克孜勒努尔组,南天山物源区逐渐向南天山造山带的腹部扩展,反映夷平作用进一步加强,构造活动性相对比较稳定。Abstract: The integration of core examination, heavy minerals, lithologic sections and relevant data has disclosed that the Early-Middle Jurassic deposits from eastern Kuqa depression in the Tarim Basin, Xinjiang are derived mostly from the southern Tianshan Mountain area. The provenance may be subdivided into four secondary source areas on the basis of heavy minerals and detratal compositions. From the Lower Jurassic Ahe and Yangxia Formations to the Middle Jurassic Kizilnur Formation, the source areas grandually expand from the southern Tianshan Mountains to the hinterland of the southern Tianshan orogenic zone, indicating the extension of leveling and relatively stable tectonic activity.