东胜气田新召东盒1段储层特征及物性影响因素  

Reservoir characteristics and influential factors of physical property:An example from Shihezi 1 Member,East Xinzhao block,Dongsheng gasfield,Ordos Basin

作　　者：荀小全[1] XUN Xiaoquan(Exploration and Development Research Institute,Sinopec North China E&P Company,Zhengzhou,Henan 450006,China)

机构地区：[1]中国石化华北油气分公司勘探开发研究院,河南郑州450006

出　　处：《天然气技术与经济》2022年第1期10-16,共7页Natural Gas Technology and Economy

基　　金：中国石油化工股份有限公司科技部科研项目“东胜气田精细表征及有效开发技术”(编号:P20065)。

摘　　要：为了明确鄂尔多斯盆地东胜气田新召东二叠系下石盒子组盒1段储层特征及储层物性影响因素,以新召东盒1段砂体为研究对象,分析了该区目的层沉积特征,进一步结合粒度分析、薄片鉴定、压汞曲线、物性测试等分析化验资料开展储层特征研究,指出了盒1段储层物性影响因素。研究结果表明:①新召东盒1段为冲积平原辫状河沉积,沉积物源主要来自北部的阴山古陆,主要发育辫流水道、心滩、河漫等沉积微相;②盒1段砂岩岩性主要为岩屑石英砂岩,孔隙类型多样,储层砂岩平均孔隙度为8.6%,平均渗透率为0.69 mD;③机械压实作用、胶结作用是最主要的破坏性成岩作用,溶蚀与微裂缝发育是最重要的建设性成岩作用。结论认为:①辫状河心滩为储层发育的有利沉积微相,储层属于低孔隙度-特低孔隙度、特低渗透率-超低渗透率型,孔喉组合以中细孔-中小喉为主。②储层物性明显受沉积作用的控制,即随着沉积水动力增强,岩石粒度增大,物性越好;储层物性也受成岩作用的控制,随着压实作用增强和胶结物含量增加,物性变差,而溶蚀作用、裂缝的发育则可以有效改善储层物性。In order to clarify the reservoir characteristics of Permian Shihezi 1 Member in East Xinzhao block,Dongsheng gasfield,and the influential factors of reservoir physical property,some sandbody of this member was taken as an objective to analyze sedimentary features.Then,the reservoir characteristics were figured out based on grain-size analysis,thin-section identification,mercury-injection curve,and physical-property test.Finally,the factors influencing the physical property of Shihezi 1 Member were determined.Results show that(1)the Shihezi 1 Member in this block belongs to braided-river deposition of alluvial plain,whose sediments are mainly sourced from the Yinshan ancient land on the north,and there mainly develop the sedimentary microfacies of braided channel,point bar,and flood plain;(2)for this member dominated by lithic quartz sandstone with various pores,the average porosity and permeability are 8.6%and 0.69 mD,respectively;and(3)both mechanical compaction and cementation are the most important destructive diagenesis whereas both dissolution and micro-fracture development are the most important constructive diagenesis.In conclusion,in the braided-river point bar which is the favorable sedimentary microfacies for reservoir development,most reservoirs are featured by low to extra-low porosity and extra-low to super-low permeability,and their pore-throat combination is mainly medium-fine pore and medium-small throat.What’s more,the physical property should be obviously affected by sedimentation,meaning that rock grain may increase to make this property better with the increase of sedimentary hydrodynamics.And the physical property is also controlled by diagenesis,which may get worse with the enhancement of compaction and cement content,but be improved effectively by dissolution and fracture development.

关 键 词：鄂尔多斯盆地 东胜气田 二叠系 储层特征 沉积作用 成岩作用 储层物性 

分 类 号：P618.13[天文地球—矿床学]