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玉东—玛东构造带位于塔里木盆地,是在中寒武统膏盐层上滑脱的大规模褶皱冲断带,内部发育多种断层相关褶皱.目前对此构造带的研究,多关注了构造带的局部以及断裂变形.本文根据断层相关褶皱理论,利用地震资料,分析了玉东—玛东构造带内构造样式上的差异性,并通过二维构造正演模拟,建立了典型构造样式的运动学模式.认为研究区内玉东、玛东、塘北3个分区,具有不同的构造样式.玉东地区主要发育和铲式逆断层相关的断弯褶皱,玛东、塘北地区则发育断层突破的滑脱褶皱,突破断层在玛东地区为铲式断裂,而在塘北地区为坪—坡—坪式断裂.根据上奥陶统变形特征及其顶面不整合面之上的地层年代,认为玉东—玛东构造带的变形始于晚奥陶世,主要断裂及其相关褶皱形成于晚奥陶世末期.玉东地区在晚奥陶世早期,形成基底—盖层的低幅褶皱,在晚奥陶世末,形成铲式断裂及断弯褶皱;玛东和塘北地区变形发生在上奥陶统沉积之后,经历了滑脱褶皱和断层突破阶段.通过对比分析认为,断层相关褶皱样式的差异,与膏盐层岩性、厚度,上奥陶统岩性、厚度及构造转换作用有关.本研究有助于完善对塔里木盆地早古生代末期构造变形及演化的认识.“,”Yudong-Madong structural belt,detached on the Middle Cambrian evaporite rocks in Tarim Basin,is a thin-skinned fold and thrust belt that has varied kinds of fault-related folds.Most studies have focused on local structures and faults.Based on fault-related folding theory,using seismic data,this study examined the geometry and kinematic of the structural styles in different areas of this structural belt and modeled the evolution of representative structures by 2-D kinematic modelling.The styles and characteristics of fault-related folds in three subareas (Yudong,Madong and Tangbei area) are varied.In Yudong,fault-bend folds form in the hanging-wall of listric thrusts.In Madong and Tangbei,the major structural style is faulted detachment folds with evaporite layers accumulated in fold cores.Breakthrough faults are mostly listric in Madong area,while in Tangbei area,breakthrough faults are greater in size and have a flat-ramp-flat geometry.The deformation of the Upper Ordovician and the age of strata above the unconformity on its top indicate that Yudong-Madong structural belt mainly developed in the Late Ordovician and first-order faults and its related folds formed in the late stage of Late Ordovician.In Yudong area,basement-cover strata formed low amplitude folds in the early stage of Late Ordovician,and listric thrust and its related fault-bend fold detaching on the Middle Cambrian evaporite rocks superimposed on the early folds in the late stage of Late Ordovician.In Madong and Tangbei area,detachment folds and their truncation came into being after the deposition of the Upper Ordovician.Folds and reverse faults underlying the evaporite layer formed in the same time with folds and thrusts above the evaporite layer respectively.Composition and thickness variations of the Middle Cambrian evaporite layer and the Upper Ordovician in the study area and structural transfer are speculated to be the factors that have controlled the difference in characteristics of fault-related fold in different sub-areas.This study would improve the understanding of the deformation and evolution of southeastern Tarim Basin during the late stage of the Early Paleozoic.