中亚与中国西部侏罗纪沉积盆地的成因分析

Formation and comparative analysis of Jurassic sedimentary basins in central Asia and western China

通过对中亚与中国西部侏罗纪大地构造格局和侏罗系沉积特征的对比分析表明 :早 -中侏罗世本地区总体处于伸展构造背景之下 ,地壳向西南方向减薄 ,海水从西南向东北方向逐渐浸漫 ;在此背景下形成了两类侏罗纪沉积盆地 ,一类是被动大陆边缘近海开阔盆地 ,存在良好的侏罗系油气生储盖组合 ,另一类是山前先断后拗的陆相盆地 ,虽然也存在侏罗系烃源岩和储层 。

Analysis of Jurassic geotectonic framework and lithofacies paleogeographical features shows that extensional tectonic controls the formation and evolution of Early Middle Jurassic sedimentary basins of central Asia and western China. The crust thins towards the southwest, and marine invades the central Asia from southwest to northeast. Such situation leads to the formation of the two kinds of Jurassic depositional basins of middle Asia and western China: (a) passive continental margin nearshore open basin, (b) piedmont fault depression basin, which have different gas oil feartures.