塔里木上二叠统沙井子组地震特征及沉积体系

Seismic Characteristics and Sedimentary Facies of Shajingzi Formation,Upper Permian in Tarim Basin

二叠纪时期,是塔里木盆地由海相沉积转为陆相沉积的关键时期,该时期盆地地质构造及沉积体系发生重大变化。前人对于塔里木盆地特定层组的研究较少,多以综合分析二叠纪层序格架为主。文章在前人研究的基础上,以上二叠统沙井子组为研究目标,通过测井、岩心、露头等证据资料,分析其地震属性特征,确定沙井子组沉积体系为三角洲-湖泊沉积体系,为典型陆相沉积,而非前人所言的陆相-海陆过渡相沉积。总结水下分流河道、席状砂、砂坝等特定沉积体地震发射特征,绘制沉积相展布,确定了东北-西南向的海退及物源供给方向,指出了优质储层的发育环境。

Permian is the critical period for the Tarim Basin to turn the continental sedimentary into marine sediments. During this period, the tectonic and depositional system has undergone huge changes. In this paper, on the basis of previous studies, mak- ing the Shajingzi formation as research goal, through logging, core, outcrop data and other evidence, analyzes the seismic characteristics and the distribution of sedimentary facies, successfully sets up the Delta - lacustrine depo- sitional system, typical continental deposits, rather than marine-continental transitional facies. It summaries the seismic characteris- tics of specific sedimentary bodies such as distributary channel, sheet sand, sand dam. Then it completes the sedimentary facies dis- tribution and determines the direction of marine regression - northeast - southwest and the direction of regressive sediment supply, pointing out the possible reservoir.