【摘要】 吐哈盆地中—下侏罗统水西沟群整体发育河流-三角洲-湖泊沉积体系，然而，盆地经历了多期构造运动改造，中—下侏罗统水西沟群沉积时期的古地貌格局，是其沉积演化特征的主控因素。综合利用钻井、地震、岩心和野外露头资料，结合前人研究工作，开展中—下侏罗统水西沟群沉积演化特征的综合分析。研究表明，中—下侏罗统水西沟群整体表现为北厚南薄的特征，由早侏罗世早期多个分离的小型沉积中心，至中侏罗世向台北凹陷迁移，形成大型统一的沉积中心。盆缘山系和盆内主要隆起的构造抬升运动塑造了中—下侏罗统水西沟群古地貌及沉积-物源格局，中—下侏罗统水西沟群沉积时期主要受南北双向物源体系的控制，其次也有来自盆内隆起的物源补给。盆地南部的古隆起形成时间早，为主要物源区，盆地南部发育远源三角洲体系。博格达局部隆起和布尔加凸起在水西沟群沉积时期持续抬升，为次要物源区。湖平面频繁升降是影响该时期沉积体系分布的另一重要因素，湖侵早期（八道湾组沉积时期）和湖退晚期（西山窑组沉积早期）盆内广泛分布三角洲平原亚相，是重要的聚煤期。三工河组沉积时期是早—中侏罗世最大的湖侵期，该时期形成了中—下侏罗统水西沟群优质的湖相烃源岩。更多还原

【Abstract】 The Lower-Middle Jurassic Shuixigou group in the Turpan-Hami Basin develops a fluvial-deltaic-lacustrine sedimentary system as a whole. However, the basin has undergone multiple tectonic movements, and the paleogeomorphological framework during the deposition of the Shuixigou group is believed to be the main factor controlling the evolution of this sedimentary system. Based on drilling, seismic, core and outcrop data, and combined with previous research, the sedimentary evolution of the Shuixigou group was comprehensively analyzed. The study shows that the Shuixigou group is generally thick in the north and thin in the south, and many small separated depocenters from the early stage of Early Jurassic to the Middle Jurassic migrated to the Taibei sag, forming a large and unified depocenter. The paleogeomorphology and sedimentation-provenance pattern of the Shuixigou group were shaped by the tectonic uplifting of the basin-margin mountains and the main bulges in the basin. The deposition of the Shuixigou group was mainly governed by both northern and southern provenances, as well as the sediment supply from the intra-basinal bulges. The early-formed paleo-bulges in the southern part of the basin served as the primary provenance, mainly owing to the distal deltaic system. The Bogda uplift and Buerga bulge, which rose continuously during the deposition of the Shuixigou group, were secondary provenances. The frequent fluctuation of lake level is another contributor to the distribution of the Shuixigou group sedimentary system. The early stage of lake transgression(the depositional period of the Badaowan formation) and the late stage of lake regression(the early depositional period of the Xishanyao formation), when delta plain subfacies was widely distributed within the basin, are critical coal-accumulation stages. The Sangonghe formation records the maximum lake transgression during the Early-Middle Jurassic, giving rise to the high-quality lacustrine source rocks of the Lower-Middle Jurassic Shuixigou group.更多还原