江汉盆地江陵凹陷南部斜坡带新沟嘴组下段滩坝成因及控制因素

Beach bar genesis of the lower member of Xingouzui Formation in the southern slope zone of Jiangling sag, Jianghan Basin, and its controlling factors

在江汉盆地江陵凹陷新沟嘴组下段沉积背景分析的基础上,结合录井、岩心、测试等资料的综合分析,探讨了江陵凹陷南部斜坡带新沟嘴组下段滨浅湖滩坝砂体的沉积特征、成因模式及控制因素。研究认为该时期滩坝砂体表现为多期发育、纵向叠置、横向迁移、连片分布的沉积特点,具有湖浪成因、环流成因和盐湖密度流成因等3种成因模式,滩坝砂体沉积受控于古基准面旋回、古地貌和古水动力等3类因素。

Based on the analysis on sedimentary setting of the lower member of Xingouzui Formation in the Jiangling sag, the Jianghan Basin, and the comprehensive analysis with mud logging, coring and testing data, the sedimentary features and genetic model of shore shallow lake beach bar sands in the lower member of Xingouzui Formation in the southern slope belt of Jiangling sag and their controlling factors were discussed. It is considered that the beach bar sands are characterized by multi-phase development, vertical superimposition, lateral migration and contiguous distribution. They correspond to three types of genetic models, including lake wave, circulation and salt lake density current. The sedimentation of beach bar sands is controlled by paleo-base level cycle, paleogeomorgraphy and paleo-hydrodynamic force.