岩相古地理特征及其与天然气分布关系——以鄂尔多斯盆地靖边西北部马五4亚段为例  

Characteristics of Lithofacies Paleogeography and Its Relationship to the Distribution of Natural Gas:A case study of sub-member Ma54,Ordovician Majiagou Formation,northwestern Jingbian area,Ordos Basin

作　　者：吴珍珍 郭艳琴 张俊杰 李百强 费世祥[3] 王起琮 杜江民 WU ZhenZhen;GUO YanQin;ZHANG JunJie;LI BaiQiang;FEI ShiXiang;WANG QiCong;DU JiangMin(School of Earth Sciences and Engineering/Shaanxi Key Laboratory of Petroleum Accumulation Geology,Xi'an Shiyou University,Xi'an 710065,China;School of Resources and Environmental Engineering,Hefei University of Technology,Hefei 230009,China;Research Institute of Petroleum Exploration and Development,Changqing Oilfield Company,CNPC,Xi'an 710018,China;Hebei Key Laboratory of Strategic Critical Mineral Resources,Hebei GEO University,Shijiazhuang 050031,China)

机构地区：[1]西安石油大学地球科学与工程学院/陕西省油气成藏地质学重点实验室,西安710065 [2]合肥工业大学资源与环境工程学院,合肥230009 [3]中国石油长庆油田公司勘探开发研究院,西安710018 [4]河北地质大学河北省战略性关键矿产资源重点实验室,石家庄050031

出　　处：《沉积学报》2023年第5期1624-1634,共11页Acta Sedimentologica Sinica

基　　金：西安石油大学研究生创新与实践能力培养计划资助(YCS21212100);国家科技重大专项(2017ZX05005002-004);陕西省重点研发计划一般项目(2023-YBGY-079);陕西省技术创新引导专项(基金)(2023-YD-CGZH-02)。

摘　　要：岩相古地理恢复是碳酸盐岩油气勘探的重要环节。为了明确岩相古地理环境与天然气分布之间的关系,以鄂尔多斯盆地西北部奥陶系马家沟组马五4亚段为例,通过岩心观察、薄片鉴定、多矿物测井解释以及“单因素分析多因素综合作图法”等多种方法,对研究区马五4亚段岩相分布、岩相古地理特征进行研究,并结合天然气层厚度及岩相古地理与天然气产能数据,探讨了岩相古地理特征与天然气分布关系。结果表明:研究区马五4亚段岩石类型主要包括泥质白云岩、膏质白云岩、白云质石灰岩和白云岩,共发育蒸发台地和局限台地两种沉积环境,蒸发台地相包括白云岩坪和含膏白云岩坪亚相,局限台地相主要包括含膏潟湖亚相。白云岩坪和含膏白云岩坪分别主要分布于研究区西北部和中部,而含膏潟湖主要展布于中东部及东南部。蒸发台地相中的含膏白云岩坪亚相是研究区马五4亚段天然气储集的最有利相带。Reconstruction of the lithological paleogeography is an important link for oil and gas exploration in carbon⁃ate reservoirs.To clarify the relationship between the paleogeography and distribution of natural gas in sub-member Ma54,Majiagou Formation,northwestern Ordos Basin,the lithology and lithofacies paleogeography were investigated by core observation,thin section identification,interpretation of mineral content in core logs,and“single-factor anal⁃ysis and multifactor comprehensive mapping”The relationship between the lithological paleogeography and the pres⁃ence of natural gas was then assessed by combining data of gas yield with the natural gas layer thickness.It was found that the main rock types in sub-member Ma54 are argillaceous dolostone,gypsum dolostone,dolomitic limestone and dolostone.The paleogeographical environment was divided into two facies:An evaporite platform and a restricted plat⁃form.Two subfacies in the former are mainly a dolomitic tidal flat and a gypsum-containing dolomitic tidal flat.The former occurs mainly in the northwestern and central parts of the study area;the latter,which reflects the develop⁃ment of a lagoon containing gypsum,occurs mainly in the central,eastern and southeastern areas.The gypsum-con⁃taining dolomitic flat in the evaporite platform is considered to have the greatest potential for natural gas retention.

关 键 词：古地理恢复 天然气分布 碳酸盐岩地层 马家沟组 鄂尔多斯盆地 

分 类 号：P618.13[天文地球—矿床学]