塔里木盆地东部地区构造特征及其演化

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

在综合地震、测井、地质等各类资料的基础上,系统分析了塔东地区的构造特征及断裂系统。塔里木盆地是一个典型的多期叠合的复合型盆地,塔东地区主要经历了四个构造演化阶段:基底形成阶段(前震旦纪)、残余古隆起形成阶段(前侏罗纪)、陆内坳陷盆地阶段(侏罗-白垩纪)、内克拉通盆地阶段(新生代)。塔东地区断裂系统的发育具有分组性、分期性的特点,北东向断裂体系形成较早(加里东-印支期),北西向和近南北向断裂体系形成较晚(印支-喜山期)。受断裂系统控制,塔东地区在垂向上可划分为前震旦系基底、古生界、中生界和新生界四大构造层,其中古生界与中新生界构造层在形成、演化上具有巨大的差异性,构造格局截然不同。在明确了构造格局与断裂系统的形成演化的基础上,进一步划分了塔东地区的三级构造单元,从而很好的指导了该区油气勘探工作的深入进展。

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 Paleozoie 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.