Based on core observation,grain size analysis,and logging facies analysis,gravity flow deposits were discovered in the 6th and the 7th member of the Triassic Yanchang Formation of the Qilicun Oilfield in the southeastern Ordos Basin.This area's main types of gravity flow deposits are slump deposits,sandy clastic flow deposits,and turbidity flow deposits.The formation process of gravity flow in the study area can be divided into five stages:delta front sedimentation stage,sliding stage,slump stage,sandy clastic flow deposition stage,and turbidity current deposition stage.Under the joint influence of the bottom shape of the lake basin,triggering mechanism,and palaeodepth,the gravity flow develops into a lake bottom fan model,and the sandy debris flow is mainly a tongue.Based on the analysis of provenance,slope,and trigger conditions,the gravity flow depositional evolution model and gravity flow sedimentary model map are established in the study area.
NETL
NSTL
维普
万方数据
