【摘要】 独山子背斜位于准噶尔盆地南缘西部,早在上世纪30年代就在背斜东部浅层新近系的沙湾组(N1s)发现了石油,是我国新疆地区发现最早的油田。该区地震成像品质差,影响了人们对独山子背斜构造特征的明确认识,导致深层(古近系及以下地层)油气勘探滞步不前。该文综合分析了地震、钻井及露头多方面资料,采用地震正演、运动学数值模拟多技术配套、分步骤实现的定量化构造建模方法,以横跨独山子背斜主体的横剖面为蓝本,确定了独山子背斜的几何学和运动学参数,最终建立了独山子构造的模型,并揭示其背斜为一三角剪切-断层传播褶皱,位于主断裂——独山子断裂上盘并受其控制;主断裂倾角为43°,断层错断白垩系吐谷鲁群(K1tg)至新近系沙湾组(N1s)地层,滑脱面为白垩系吐谷鲁群塑性地层,前翼发育剪切三角变形区,顶角为25°。该模型有效降低了独山子背斜构造认识的多解性并表明:独山子背斜中-上侏罗统油气储集层与下白垩统盖层组成的储盖组合成藏条件较好,是下一步油气勘探的现实领域。该方法对我国中西部前陆冲断带广泛发育的断层相关褶皱的研究具有一定的借鉴意义。更多还原

【Abstract】 The Dushanzi anticline is located at the southwestern margin of Junggar basin. Oil was found in shallow Shawan formation (N1s) in the east of the anticline, in the early 1930s. It , s the first oil field of Xinjiang region, China. Due to the poor quality seismic imaging, the structural characteristics of the anticline is not thoroughly understood. Therefore, there has been little progress in oil and gas exploration in deeper formations. This paper puts forward a quantitative structure modeling method, which consists of two steps with comprehensive information (seismic,drilling and outcrop data) and two crucial techniques (the seismic modeling and kinematics simulation). A seismic section across the Dushanzi anticline was selected as a chief source. The geometric and kinematic parameters of the Dushanzi anticline have been determined, and quantitative structure model was established by using this method. Dushanzi anticline is a trishear-fault propagation fold,located on the hanging wall of the Dushanzi faultwith 43° dip, and comes into being in the mudstone of the Tugulu formation (K1tg); the strata from Tugulu formation (K1tg)to Shawan formation(N1s)were cut off by the fault. The shear deformation area exists in the front limb with a dip angle of 25°. The multiple solutions of Dushanzi anticline are effectively reduced by quantitative structure modeling. The new quantitative model indicates that the lower-middle formations of the Dushanzi anticline has better reservoir prospecting, which is also reasonable to be the further exploration target. This method also has some practical significance in the study for fault-related folds which are widely distributed in western China.更多还原