Structural Characteristics and their Significance for Hydrocarbon Accumulation in the Northern Slope of the Central Sichuan Paleo-uplift  

作　　者：TIAN Xingwang LIU Guangdi LUO Bing YANG Yu WEN Long ZHANG Benjian CHEN Xiao SU Guiping SONG Zezhang PENG Hanlin ZHOU Gang YAN Wei YANG Dailin WANG Yunlong SUN Yiting DOU Shuang 

机构地区：[1]State Key Laboratory of Petroleum Resources and Prospecting,China University of Petroleum,Beijing 102249,China [2]College of Geosciences,China University of Petroleum,Beijing 102249,China [3]Research Institute of Exploration and Development,Southwest Oil and Gas Field Company,PetroChina,Chengdu 610041,China

出　　处：《Acta Geologica Sinica(English Edition)》2022年第4期1451-1470,共20页地质学报（英文版）

基　　金：funded by the National Key Research and Development Program‘Deep Land Resources Exploration and Exploitation’special project(2017YFC0603106);the Project of Science and Technology Department of the Southwest Oil and Gas Field Company,Petrochina(20210301-02)。

摘　　要：Based on 2D and 3D seismic data,the latest drilling data and field outcrop data of the northern slope of the Central Sichuan paleo-uplift,the structural analysis method is used to analyze unconformity development characteristics and fault characteristics during the key structural transformation period,discussing the influence of the structural characteristics on the hydrocarbon accumulation of deep carbonate rocks.The results show that:(1)The two key unconformities of the Tongwan and Caledonian periods were primarily developed in deep carbonate rocks.Firstly,Tongwan’s unconformities are characterized by regional disconformities between the second and third members of the Dengying Formation,the top formation of the Sinian and the lower Cambrian,strips of which zigzag through the north and south sides of the study area.Secondly,the Caledonian unconformity is characterized by a regional unconformable contact between the lower Permian and the ower Paleozoic strata.From NE to SW,the age of the strata,which were subject to erosion,changes from new to old,the denudation distribution showing as a nose-shaped structure which inclines towards the ENE.(2)Boundary fault and transtensional strike-slip faults developed in the Sinian to Paleozoic strata.In profile,there are three types of structural styles:steep and erect,flower structures,’Y’and reversed’Y’type faults.In plane view,the Sinian developed extensional boundary faults extending in an almost NS direction,strike-slip faults developing and extending linearly in approximately EW,WNW and NE strikes in the Cambrian,with characteristically more in the south and less in the north.(3)The faults in the northern slope show obvious zonal deformations in transverse view as well as significant stages and stratified activity in a longitudinal direction.Among them,the activity of faults in the Sinian was the strongest,followed by the activity in the Cambrian period,the activity intensity of faults in the Permian period being the weakest.This fault activity can be divided

关 键 词：northern slope of paleo-uplift UNCONFORMITY structural characteristics hydrocarbon accumulation Central Sichuan paleo-uplift Sichuan Basin 

分 类 号：P618.13[天文地球—矿床学]