Relationship between Natural Fracture and Structural Style and its Implication for Tight Gas Enrichment:A Case Study of Deep Ahe Formation in the Dibei–Tuzi Area,Kuqa Depression  

作　　者：XIA Lu XI Kelai YANG Xianzhang HAN Zhanghua XU Zhenping ZHOU Lu YU Guoding WANG Daoshen WANG Weiyu 

机构地区：[1]School of Petroleum Engineering,Shandong Institute of Petroleum and Chemical Technology,Dongying,Shandong 257061,China [2]National Key Laboratory of Deep Oil and Gas,China University of Petroleum(East China),Qingdao,Shandong 266580,China [3]Research Institute of Petroleum Exploration and Development,PetroChina Tarim Oilfield Company,Korla,Xinjiang 841000,China

出　　处：《Acta Geologica Sinica(English Edition)》2024年第4期1086-1110,共25页地质学报（英文版）

基　　金：granted by Petro China Major Science and Technology Project(Grant No.ZD2019-18301-003);Natural Science Foundation of Shandong Province(Grant No.ZR2023MD069);Training Program of Innovation for Undergraduates in Shandong Institute of Petroleum and Chemical Technology(Grant No.2022084);Science Development Foundation of Dongying(Grant No.DJ2020007)。

摘　　要：The deep Lower Jurassic Ahe Formation(J_(1a))in the Dibei–Tuzi area of the Kuqa Depression has not been extensively explored because of the complex distribution of fractures.A study was conducted to investigate the relationship between the natural fracture distribution and structural style.The J_(1a)fractures in this area were mainly high-angle shear fractures.A backward thrust structure(BTS)is favorable for gas migration and accumulation,probably because natural fractures are more developed in the middle and upper parts of a thick competent layer.The opposing thrust structure(OTS)was strongly compressed,and the natural fractures in the middle and lower parts of the thick competent layer around the fault were more intense.The vertical fracture distribution in the thick competent layers of an imbricate-thrust structure(ITS)differs from that of BTS and OTS.The intensity of the fractures in the ITS anticline is similar to that in the BTS.Fracture density in monoclinic strata in a ITS is controlled by faulting.Overall,the structural style controls the configuration of faults and anticlines,and the stress on the competent layers,which significantly affects deep gas reservoir fractures.The enrichment of deep tight sandstone gas is likely controlled by two closely spaced faults and a fault-related anticline.

关 键 词：fracture distribution structural style deep tight sandstone electrical image logging Kuqa Depression Tarim Basin 

分 类 号：P618.13[天文地球—矿床学]