The Tectonic Characteristics and Its Evolution in The Eastern Tarim Basin,Xinjiang

Based on the seismic data,log interpretation,geological and other information,we have systematically analyzed the structural characteristics and the fault system of the eastern Tarim basin.It is well established that Tarim basin is a largely composite and superimposed sedimentary basin,and its east part has mainly undergone four stages of tectonic evolution including the formation of the basement(Pre-Sinian),the formation of the residual palaeohigh(Pre-Jurassic),the intacontinental depression(Jurassic-Cretaceous)and the inner Cratonization(Cenozoic).The fault system of the eastern Tarim basin shows the Characteristics of grouping and staging.For instance,the NE-trending fault system formed earlier(Caledonian-Indochina),while the NW-trending and nearly S-N direction fault systems formed late(Indochina-Yanshanian).As a result of regional structure controlling on the fault system of the eastern Tarim basin,four structure layers can be divided in the vertical direction:the pre-Sinian basement,Paleozoic,Mesozoic and Cenozoic structure layers.Thereinto,there is a prominant difference in formation and evolution among Paleozoic and Mesozoic,Cenozoic tectonic layers.On the basis of the clear structure and fault system in the eastern Tarim basin,this area is further devided into third-level tectonic element.Hence,this is favourable for further exploration for oil and gas.