湖北潜江盐湖盆地潜江组储层物性影响因素分析  

Influencing Factors of Reservoir Physical Properties of Qianjiang Formation in Qianjiang Salt Lake Depression

作　　者：郭丽彬 黄华 赵文 GUO Li-Bin;HUANG Hua;ZHAO Wen(Exploration&Development Research Institute of SINOPEC Jianghan Oilfield Branch Company,Wuhan 430223,Hubei,China;China University of Geosciences(Wuhan),Wuhan 430074,Hubei,China;Exploration management department of SINOPEC Jianghan Oilfield Branch Company,Qianjiang 433100,Hubei,China)

机构地区：[1]中石化江汉油田分公司勘探开发研究院,湖北武汉430223 [2]中国地质大学(武汉),湖北武汉430074 [3]中石化江汉油田分公司勘探管理部,湖北潜江433100

出　　处：《华南地质》2024年第1期75-84,共10页South China Geology

基　　金：中国石油化工股份有限责任公司科研项目(P21106)。

摘　　要：湖北潜江盐湖盆地储集类型有别于我国东部其它断陷盆地。本文以古近系潜江组储集层为研究对象,对大量样品储集物性分析测试、薄片镜下观察和成岩作用研究并结合勘探实践成果,研究潜江盐湖盆地特有的储集类型及其物性的影响因素。结果表明潜江盐湖盆地潜江组主要发育砂岩、含碳酸盐砂岩和碳酸盐质砂岩三类有利常规油气储层,其中砂岩储层平面上主要分布于砂泥岩相区,含碳酸盐砂岩和碳酸盐质砂岩平面上主要分布于过渡岩相区。除压实作用外,沉积相带、胶结和溶蚀作用是控制三类储层储集物性的主要因素。水下分支河道、河口坝和席状砂等沉积微相砂岩表现为中孔中渗,孔渗性较好,过渡岩相区的含碳酸盐砂岩和碳酸盐质砂岩主要为低孔低渗,孔渗性较差。白云石、方解石、硬石膏等胶结物的发育严重破坏了砂岩储层原始粒间孔隙,造成储层孔渗性变差。生烃阶段形成的有机酸可以溶蚀早期碳酸盐胶结物,形成次生溶蚀孔隙,在一定程度上改善了储层孔渗性。在此溶蚀机制下,结合生烃增压作用,研究区含碳酸盐砂岩和碳酸盐质砂岩具有一定储集能力,可以作为隐蔽性油藏有效储集层。The reservoir types of Qianjiang Salt Lake Depression are different from other Eastern Basins.Taking the Paleogene Qianjiang Formation reservoir as the research object,this article analyzes the reservoir properties of a large number of samples,observes thinsection under microscope,and studies diagenesis to define the unique reservoir types and their influencing factors in the Qianjiang Salt Lake Basin combining with exploration practice results.Sandstones,carbonate bearing sandstones and carbonate sandstones are considered as favorable conventional oil and gas reservoirs.Sandstone reservoirs are mainly distributed in sandstone and mudstone facies areas,while carbonatebearing sandstones and carbonate sandstones are mainly distributed in transitional lithofacies areas.And the physical properties of the three types reservoirs are mainly affected by sedimentary microfacies,cementation,dissolution besides compaction..Sedimentary microfacies sandstones such as underwater branching channels,estuarine dams,and sheet sand exhibit medium porosity and good permeability,while carbonate bearing sandstone and carbonate sandstone in the transitional zone are of mainly low porosity and poor permeability.The development of dolomite,calcite,anhydrite and other cements seriously damaged the original intergranular pores of sandstone reservoirs,resulting in poor porosity and permeability of reservoirs.The organic acids formed during the hydrocarbon generation stage can dissolve early carbonate cements,forming secondary dissolution pores,and to some extent improving reservoir porosity and permeability.Under this dissolution mechanism,combined with hydrocarbon generation and pressure boosting,it is believed that carbonate bearing sandstone and carbonate sandstone have certain reservoir capacity and can serve as effective and subtle oil reservoirs in the study area.

关 键 词：潜江盐湖 潜江组 储层物性 影响因素 

分 类 号：TE122.1[石油与天然气工程—油气勘探] P618.130.2[天文地球—矿床学]