天然气勘探与开发2023，Vol.46Issue(4)：1-12,12.DOI:10.12055/gaskk.issn.1673-3177.2023.04.001
四川盆地二叠、三叠系构造—沉积特征及有利勘探区带
Permian and Triassic in Sichuan Basin:Tectono-sedimentary characteristics and favorable exploration belts
摘要
Abstract
The Permian system in Sichuan Basin is complex in tectono-sedimentary evolution,creating difficulties in restoring the distribution of favorable facies zones and uncertainties in favorable exploration belts.So,through the latest 2D and 3D seismic data as well as drilling and mud-logging data in and around the basin,this evolution was investigated systematically to identify response char-acteristics and influential factors of major tectonic movements.The relationship of continuous sedimentary evolution was established to every formation and member and the distribution of favorable facies zones with multiple targets was defined to provide an import-ant support for optimizing the favorable exploration belts.After the comprehensive analysis on geological characteristics,it is revealed that(i)multiple factors,including ancient landform before the Permian deposition,and tensile tectonic setting,mantle plume uplift and volcanic eruption in the Permian,affect the tectonic-sedimentary differentiation of the Permian;(ii)representing a regional tensile tectonic setting,the Permian in Sichuan Basin was a sedimentary system of cratonic rifted basin,which controlled the distribution of bioreef-beach facies zones on the margin of multiple strata,laying a foundation for the development of massive lithologic traps;(iii)in the early Triassic,the basin inherited the sedimentary pattern in the late Permian,and exhibited one feature of filling and leveling up due to some effects,for example,ancient land,island chain and underwater uplift at the basin margin.It was a sedimentary system of cratonic depression basin,whose beaches in vertical and lateral accretion might be controlled by microgeomorphology and presented large-scale sheet-like distribution in Qingshuitai area in plane;and(iv)dependent on the analysis of tectono-sedimentary setting and the comprehensive application of 2D and 3D seismic data,the main sedimentary features were defined,such as"one margin and two ribbons"in Qixia Formation,"one uplift and one margin"in Maokou Formation,"three uplifts and three depressions"in Changxing Formation,and"three uplifting forming beaches and three depressions filling and leveling up"in Feixianguan Formation.In addition,the analysis of petroleum geology points that the main exploration domains and prospects of Permian-Triassic in Sichuan Basin will focus on the platform margin zone of Qixia Formation in western basin,the intraplatform highland zone in central-southern basin,the platform margin zone of Maokou Formation in Jian'ge-Nanchong-Shizhu area,the trough in Kaijiang-Liangping area,and the bioreef-beach on the edge of Changxing Formation in shallow shelf of Pengxi-Wusheng-Shizhu area.关键词
四川盆地/二叠系—三叠系/构造—沉积特征/油气勘探/有利区带Key words
Sichuan Basin/Permian-Triassic/Tectonic-sedimentary characteristics/Petroleum exploration/Favorable exploration belt引用本文复制引用
文龙,张本健,陈骁,徐亮,马华灵,彭瀚霖..四川盆地二叠、三叠系构造—沉积特征及有利勘探区带[J].天然气勘探与开发,2023,46(4):1-12,12.基金项目
国家科技重大专项下属课题"四川盆地二叠系—中三叠统天然气富集规律与目标评价(编号:2016ZX05007-004)",中国石油天然气股份有限公司重大科技专项"四川盆地二、三叠系天然气富集区带评价(编号:2016E-0603)"、中国石油西南油气田科技项目"四川盆地二叠系构造沉积演化特征及勘探区带评价研究(编号:20230301-04)". （编号:2016ZX05007-004）
