塔里木盆地西南坳陷东部构造特征及对油气成藏的控制

Characteristics of fault structure and its control on hydrocarbon accumulation in the eastern part of southwestern Tarim Basin

运用断层相关褶皱理论对位于塔西南坳陷东部的玛扎塔格、玉北1及和田南构造带进行了几何学与运动学特征分析。研究表明,玛扎塔格断裂带主要发育深浅2套断裂系统,深部断裂系统形成断层传播褶皱,浅层为冲断构造;玉北1构造带构造变形主要集中在古生界,发育复合叠加型断层传播褶皱;位于西昆仑山前的和田南断裂带为逆冲前缘带,由多个滑脱层共同作用形成构造楔。加里东晚期—海西早期、海西晚期及喜马拉雅期是影响该地区构造形成和演化的主要时期。该地区油气成藏受断裂控制影响明显,喜马拉雅期该地区的地层发生大规模掀斜改造,使得麦盖提斜坡枢纽部位与巴楚隆起南缘构造带成为油气富集的有利区带。

High resolution interpretations of seismic profiles in the eastern part of southwestern Tarim Basin have been accomplished with the application of fault-related folding geometry principles. The Mazhatage fault zone developed both shallow and deep fault systems,and formed fault propagation folds in the deep fault system and thrust structures in the shallow fault system. The Yubei1 tectonic zone was deformed in the Paleozoic strata,and developed mixed fault propagation folds. The Southern Hetian thrust and nappe fault zone is located in front of the western Kunlun orogeny,and developed structural wedges. The Late Caledonian-Early Hercynian,Late Hercynian and Himalayan periods are important for structural formation and evolution in this area. Faults controlled hydrocarbon accumulation in the study area. A large-scale tilting movement took place in the study area during the Himalayan period. Therefore,the pivot part of Maigaiti slope and the southern margin of Bachu uplift are hydrocarbon enrichment zones.