【摘要】 近岸水下扇是塔南凹陷下白垩统南屯组最重要的沉积体系,发育于断层坡度陡、物源近的深湖环境。通过岩心观察和三维地震解释,结合区域构造背景将研究区近岸水下扇划分为3个亚相:内扇、中扇和外扇。沉积构造主要为递变层理、重荷模、火焰构造、泄水构造、包卷层理,鲍马序列发育。沉积相发育主要受同沉积断裂活动控制。更多还原

【Abstract】 Nearshore subaqueous fans develop in the Nantun formation of lower Cretaceous from Tanan depression in Mongolia.Nearshore subaqueous fans occur in the steep slope and in the proximal provenance.By observing core samples and applying 3-D seismics,nearshore subaqueous fans are subdivided into three subfacies which consist of inner fan,middle fan and outer fan.Sedimentary structures include graded bedding,load casts,flame structures,water-escape structure,convolute bedding,and Bouma sequences also develop.The sedimentary distribution was controlled by syndepositional faults.更多还原