海相油气地质2025，Vol.30Issue(2)：119-132,14.DOI:10.3969/j.issn.1672-9854.2025.02.003
鄂尔多斯盆地寒武纪层序岩相古地理特征及对储集体的控制作用
Lithofacies paleogeographic characteristics of Cambrian sequence and their control over reservoir in Ordos Basin
摘要
Abstract
The Cambrian in Ordos Basin has the potential for natural gas exploration.To clarify the distribution pattern of favorable sedimentary facies zones and reservoirs,by comprehensively analysing core,outcrop and seismic data,two types of sequence boundaries,unconformities and lithological transition surfaces are have been identified in the Cambrian of the Ordos Basin.The Cambrian strata can be divided into two 2nd-order sequences(SS1,SS2)and eight 3rd-order sequences(SQ1-SQ8),each 3rd-order sequence consists of a TST and a HST,lacking a LST.The unconformity surfaces of the bottom and top of the Cambrian system serve as the bottom and top boundaries of SS1 and SS2.The lithological transition surface is the 3rd-order sequence boundary.Eight lithofacies palaeogeoguaphic maps were systematically compiled to analyze the lithofacies paleogeographic distribution characteristics under 3rd-order sequence stratigraphic framework of Cambrian in Ordos Basin.The Cambrian in the Ordos Basin has gone through two sedimentary stages.SQ1-SQ4 is the stage of transgression,developing carbonate ramp sedimentary system.SQ5-SQ8 is the stage of regression,developing shallow water carbonate platform sedimentary system.Controlled by the evolution of sequence lithofacies paleogeography,the Cambrian reservoirs in Ordos Basin are mainly distributed longitudinally in SQ6-SQ8,and the good reservoirs of Cambrian in Ordos Basin include three types:dolomitizational oolitic shoal reservoir,supergene karst reservoir and fault-dissolution reservoir.Due to the control of the platform margin and high-level system tract,as well as the distribution and faulting of ancient uplifts,the oolitic shoal reservoir is mainly distributed in the western and southern platform margin of the basin,the supergene karst reservoir is distributed in the periphery of the palaeouplift,and the fault-dissolution reservoir is isolated in the basin.关键词
层序/岩相古地理/沉积体系/储集体/寒武纪/鄂尔多斯盆地Key words
sequence/lithofacies palaeogeography/sedimentary system/reservoir/Cambrian/Ordos Basin分类
石油、天然气工程引用本文复制引用
卢意,张春林,由雪莲,聂宇晗..鄂尔多斯盆地寒武纪层序岩相古地理特征及对储集体的控制作用[J].海相油气地质,2025,30(2):119-132,14.基金项目
本文受中国石油"十四五"重大科技项目"鄂尔多斯盆地风险勘探领域和目标研究、工程技术攻关及现场试验"(编号:2023YQX10105),中国科学院战略性先导科技专项(A类)"深层油气形成与分布预测"(编号:XDA14010403)和国家科技重大专项"大气田富集规律与勘探关键技术"(编号:2016ZX05007-002)联合资助 （编号:2023YQX10105）
