塔里木盆地奥陶系礁滩相储集体特征

塔里木盆地奥陶系多个地区发育礁滩相储集体。综合分析露头、岩心、岩石薄片及相关测试数据,对礁滩相储集体的发育条件及储集性能进行了研究。结果表明:礁相与滩相常以复合伴生的形式存在,根据滩相的岩性特征可将台地边缘划分为低能、相对低能、相对高能及高能4种类型,骨架礁、障积礁、灰泥丘所代表的台地边缘水动力条件依次降低。礁滩储集体基质孔渗性差,储集空间以裂缝—孔洞型为主,其次是裂缝—孔隙型、孔洞型、裂缝型和复合型。古地貌与构造控制了礁滩储集体的发育,而岩溶、构造破碎等建设性成岩作用是礁滩相灰岩形成良好储集体的必要条件。

Research on the Characteristics of Reef-bank Reservoirs in Ordovician, Tarim Basin

Reef-bank reservoir in Ordovician has been discovered in several areas,Tarim Basin.Crop,core,thin section and test data indicate that the bank face always accompanies with reef face.Platform edge can be divided into four types according to the lithologic characteristic of bank face,including low energy environment,relatively low energy environment,relatively low energy environment and high energy environment.Framework reef,baffle-reef and lime mud mound represent the environment energy decreasing.Data shows that original reef-bank reservoirs reveal low porosity and permeability and reservoir space is dominated by cavity-fractured type,followed by cavity-freckle type,cavern type,freckle type and complex type.The development of reef-bank reservoirs is controlled by Palaeogeomorphology and structure while high quality reservoirs determined by karstification and clastation.