鄂尔多斯盆地新安边地区延10辫状河相砂体构型研究

Study on The Configuration of 10-Braided Fluvial Sand Body in Xin’anbian Area of Ordos Basin

对于辫状河相砂体构型的研究,以新安边地区延10储层为例,运用铸体薄片、压汞法和常规的物性分析,结合岩心和测井曲线资料等对沉积相的确定以及对隔夹层的识别.结果表明:新安边地区延10储层发育砂质辫状河相,其微相包括心滩、河道和泛滥平原,岩性发育以长石石英砂岩和岩屑石英砂岩为主;储集空间主要是以粒间孔和长石溶孔为主;研究区隔夹层较为分布且隔夹层具有明显的区别,泥质隔夹层较多其次为物性隔夹层和钙质隔夹层,且泥质隔夹层厚度相对较大;辫状河砂体构型以多期型M和两期型D为主,其中河道微相以D2和S发育为主,厚度多在5~8 m之间,心滩微相以M型发育为主,其厚度大于9 m.该研究成果对于砂质辫状河相后期油气勘探开发具有重要意义.

For the study of the configuration of braid fluvial sand,taking the Yan10 reservoir in Xin’anbian area as an example,casting sheets,mercury pressure method and conventional physical property analysis were used to determine the sedimentary facies and identify the compartment interlayer by combining core and logging curve data.The results showed that sandy braided fluvial facies developed in Yan10 reservoir in Xin’anbian area,and its micro-facies included heart beach,river channel and floodplain,and lithological development was dominated by feldspar quartz sandstone and rock chip quartz sandstone.The storage space is mainly composed of intergranular pores and feldspar karst pores.The study was divided into more distributed and the septum interlayers were clearly different,followed by physical intersections and calcareous interlayers,the thickness of argillaceous interlayers was relatively large.The configuration of braided river sand body was mainly multi-stage M and two-stage D,among which the river channel micro-facies were mainly developed by D2 and S,the thickness was mostly between 5-8 m,and the heart beach micro-facies were mainly developed in M-type,and its thickness was greater than 9 m.The research results are of great significance for the exploration and development of oil and gas in the late stage of sandy braided fluvial facies.