惠民凹陷临 7 断块区沙三段沉积相分析

针对研究区沉积相认识不清等问题，在岩心观察的基础上，利用区域地质、分析化验和测井等资料 系统研究了惠民凹陷临 7 断块区沙三段沉积相，认为研究区发育三角洲相、浊积扇相、湖泊相，其中三角 洲相包括水下分支河道、支流间湾、分支河口砂坝、远砂坝及前三角洲泥等 5 种微相，浊积扇相包括沟道、沟 道间、沟道前缘、沟道侧缘及外扇泥等 5 种微相，湖泊相主要发育半深湖—深湖泥微相。 平面上，三角洲、 沟道沉积均沿北西—南东向展布；垂向上，沙三下亚段发育三角洲沉积，沙三中、上亚段发育浊积扇、半深 湖—深湖沉积。 从沙三下到沙三上沉积期，砂体反复进积、退积，并逐渐由西向东移动，研究区水体虽也有 短暂下降，但总体呈上升趋势。 开展临 7 断块区沙三段沉积微相分析，为储层综合研究提供了地质依据

Study on sedimentary facies of the third member of Shahejie Formation in Lin 7 fault block,Huimin Sag

Based on core observation, combining with data of regional geology, analysis assay and well logging, this paper systematically studied the sedimentary facies of the third member of Shahejie Formation （ Es ₃ ） in Lin 7 fault block of Huimin Sag. It is considered that the study area developed delta, turbidite fan and lacustrine facies. The delta can be further divided into microfacies of underwater distributary channel, interdistributay bay, mouth bar, distal bar and prodelta mud, the turbidite fan can be further divided into microfacies of channel, interchannel, lateral frontchannel, margin channel and outer fan mud, and the lacustrine facies mainly developed semi-deep to deep lake mud. In the plan, the sediment in Es ₃ spreaded along WN-ES direction. In vertical profile, the delta deposite mainly developed in lower Es ₃ , the turbidite fan and the semi-deep to deep lacustrine mainly developed in middle and upper Es ₃ . From lower Es₃ to upper Es ₃ , sand body experienced progradation to retrogradation repeatedly, and moved from west to east gradually, and the water is deepening gradually on the whole, including some short decreasing. This study of sedimentary microfacies provides geological basis for the comprehensive reservoir research of Es ₃ in Lin 7 fault block.