鄂尔多斯盆地延安西部地区马五_(1+2)亚段正向低幅度构造成因及油气地质意义  

Genesis and gas control mechanism of positive low-amplitude structure in the Ma_(5)^(1+2) sub-member in western Yan'an,Ordos Basin

作　　者：冯林杰 蒋裕强[1,2] 武富礼 武渝 梁德民 FENG Linjie;JIANG Yuqiang;WU Fuli;WU Yu;LIANG Demin(School of Geoscience and Technology,Southwest Petroleum University,Chengdu 615000,China;Reservoir Evaluation Laboratory,CNPC Key Laboratory of Unconventional Oil&Gas,Chengdu 615000,China;School of Geoscience and Engineering,Xi’an Shiyou University,Xi’an 710065,China;Research Institute of Petroleum(Group)Co.,Ltd.,Xi’an 710065,China)

机构地区：[1]西南石油大学地球科学与技术学院,四川成都610500 [2]中国石油天然气集团公司非常规油气重点实验室储层评价研究室,四川成都610500 [3]西安石油大学地球科学与工程学院,陕西西安710065 [4]延长石油(集团)有限责任公司研究院,陕西西安710065

出　　处：《天然气地球科学》2022年第6期944-954,共11页Natural Gas Geoscience

基　　金：国家自然科学基金(面上项目)“基于成岩系统剖析的致密砂岩储层差异致密化机理及渗流差异响应研究”(编号:cstc2021jcyjmsxmX0897)资助。

摘　　要：为查明鄂尔多斯盆地延安西部地区马五_(1+2)亚段低幅度构造成因及其与油气富集的关系,在采用趋势面分析法对现今低幅度构造精细识别的基础上,开展了古地貌与现今构造对比,并结合钻井、测井、试气以及铸体薄片资料对正向低幅度构造成因及石油地质意义进行了初步探讨。结果表明:①该区马五_(1+2)亚段顶面共发育10处正向低幅度构造,形态以鼻隆为主,构造轴线具有近东—西、近北东—南西、近北西—南东3种走向;②现今西倾单斜背景下的正向低幅度构造主要由早石炭世岩溶古地貌高部位继承性演化而来;③正向低幅度构造与优质储层分布在马六段灰岩缺失区具有一定的耦合性;④正向低幅度构造的发育有利于构造—岩性圈闭的形成,对天然气的富集具有关键的控制作用。In order to find out the genesis of low-amplitude structure in Ma_(5)^(1+2) sub-member in western Yan'an and its relationship with oil and gas enrichment,based on the fine identification of current low amplitude structure by trend surface analysis,this study carried out the comparison between paleogeomorphology and current structure,and preliminarily discussed the genesis and petroleum geological significance of positive low-amplitude structures in combination with drilling,logging,gas testing and cast thin section data.The results show that:(1)A total of 10 positive low-amplitude structures are developed on the top of Ma_(5)^(1+2) sub-member in this area,mainly in the form of nose uplift,and the structural axis has three trends:Near east-west,near northeast-southwest and near northwest-southeast;(2)The positive low-amplitude structure under the current west dipping monocline background is mainly inherited and evolved from the high parts of pre-Carboniferous karst paleogeomorphology;(3)There is a certain coupling between the positive low-amplitude structure and the distribution of high-quality reservoirs in the limestone deficient area of Ma6 Member;(4)The development of positive low-amplitude structures is conducive to the formation of structural-lithologic traps and has an obvious control over the enrichment of natural gas.

关 键 词：鄂尔多斯盆地 延安西部地区 正向低幅度构造 岩溶古地貌 油气富集 

分 类 号：TE121.1[石油与天然气工程—油气勘探]