麻黄山西区块延8储层研究

Reservoir study on the eighth member of Yan’an Formation in the west of
Mahuangshan Region

王少飞

Wang Shaofei

华北分公司勘探开发研究院，河南 郑州 450006

Research Institute of Exploration and Development, North China Oilfield Company, SINOPEC, Zhengzhou 450006, China

通过对区块内多口探井的分析研究,认为该区侏罗系延安组延8油层组为河流-沼泽相沉积，河道砂体是本区块油气的主要储集类型。东12、13井区储层类型以长石砂岩为主，岩屑长石砂岩次之；成分成熟度低为主，结构成熟度中等偏低。东15井区储层类型则主要是岩屑石英砂岩；成分成熟度以中偏高为主，结构成熟度中等偏低。该区块储层次生孔隙类型以粒间残余孔为主，粒内溶蚀孔次之，含有少量的铸模孔。按储层性质对侏罗系储层进行分类评价，划分出4种储层类型，综合评价认为延8油层组储层主要为Ⅰ—Ⅱ类储层。

The west of Mahuangshan Region lies in the west of Tianhuan Depression of Ordos Basin. Through the analysis of many exploitation wells, it is convinced that the eighth member of Jurassic Yan忆an Formation in Mahuangshan Region is a set of fluvial-swamp facies sedimentation. The channel sand is the main style of oil storage. The rock type in well groups of Dong12 and Dong13 is mainly of arkose and secondarily of cuttings feldspar sandstone, in which compositional maturity is in lower level and the textural maturity is in medium low level. And the lithic quartz is the main rock type in Dong15 well group, in which compositional maturity is in medium high level and the textural maturity is in medium low level. The chief induced porosity is mainly intergranular residual porosity and secondarily is intragranular dissolution porosity, and also
including little amount of moldic pores. Four kinds of reservoirs are divided in Jurassic according to the characteristics of reservoirs. It is convinced in comprehensive evaluation that the main types of reservoirs are Ⅰ^_Ⅱin the eighth member of Yan’an Formation in the Mahuangshan Region.