鄂尔多斯盆地马五段膏盐岩沉积对天然气成藏的影响  

Influences of gypsum-salt deposition on gas accumulation of the fifth member of Majiagou Formation in Ordos Basin

作　　者：孙玉景 周立发[1,2] SUN Yujing;ZHOU Lifa(Department of Geology,Northwest University,Xi’an 710069,China;State Key Laboratory of Continental Dynamics,Xi’an 710069,China)

机构地区：[1]西北大学地质学系,西安710069 [2]大陆动力学国家重点实验室,西安710069

出　　处：《岩性油气藏》2018年第6期67-75,共9页Lithologic Reservoirs

基　　金：国家重点基础研究发展计划专项基金资助项目"鄂尔多斯盆地奥陶系马家沟组大规模实施二氧化碳地质封存的综合研究与数值模拟"(编号:2016YFE0102500)资助

摘　　要：马家沟组马五段是鄂尔多斯盆地奥陶系的主力天然气勘探层段,研究该层段膏盐岩沉积对天然气成藏的影响有助于气田进一步的勘探开发。利用岩心、薄片及其他统计分析资料,对马家沟组马五段膏盐岩的特征、成因及其对气藏的影响进行了综合研究。结果表明:研究区马五段膏盐岩主要是石膏岩和膏溶角砾岩,属于蒸发成因;马五段膏盐岩的沉积有利于有机质的保存和烃类物质的生成,有利于保持并提高其下部岩层的孔隙度,具有良好的封盖能力,有助于天然气的运移、聚集和保存,对马五段气藏的形成具有重要影响。该研究成果对类似地区膏盐岩沉积对天然气成藏影响的研究具有借鉴意义。The fifth member of Majiagou Formation(Ma 5 member)is the main gas exploration layer of Ordovician in Ordos Basin.Studying the influences of gypsum-salt deposition on gas accumulation is helpful to the further exploration and development of gas field.The data of cores,thin sections and other statistical analysis were used to study the lithology characteristics and genesis of gypsum-salt rocks of Ma 5 member,as well as its influences on gas reservoir.The results show that the gypsum-salt rocks in Ma 5 member mainly consist of gypsum and gypsum karst breccia,which belong to evaporative genesis.The deposition of gypsum-salt rocks in Ma 5 member is conducive to the organic matter preservation and hydrocarbon generation,and to maintaining and improving the porosity of the lower strata.It also has good sealing ability,and is beneficial for the migration,accumulation and preservation of gas.It is believed that the gypsum-salt deposition in Ma 5 member plays a significant role in the formation of gas reservoirs.This research result is of great importance for the study on the influences of gypsum-salt deposition on natural gas accumulation in similar areas.

关 键 词：膏盐岩 蒸发成因 气藏 马五段 奥陶系 鄂尔多斯盆地 

分 类 号：TE122.1[石油与天然气工程—油气勘探]