川西坳陷孝泉-新场地区须家河组四段储层控制因素及预测地质模型  

Reservoir controlling factors and geological prediction models of the 4^(th) member of the Xujiahe Formation in Xiaoquan-Xinchang area,the western Sichuan Basin

作　　者：孟万斌[1] 吕正祥[2] 刘家铎[1] 田景春[1] 冯明石[1] 李敏 

机构地区：[1]成都理工大学油气藏地质及开发工程国家重点实验室,四川成都610059 [2]成都理工大学能源学院,四川成都610059 [3]广西壮族自治区272地质队,广西南宁530023

出　　处：《石油与天然气地质》2013年第4期483-490,共8页Oil & Gas Geology

基　　金：国家科技重大专项(2008ZX05002-004-002);油气藏地质及开发工程国家重点实验室项目(国家科研G9)

摘　　要：利用岩石薄片、扫描电镜、阴极发光等技术方法,结合储层物性、沉积相等资料,对川西坳陷孝泉-新场地区须家河组四段储层发育的控制因素和储层预测地质模型进行了研究。结果表明,该区须四段储层岩石类型主要为岩屑砂岩、岩屑石英砂岩、钙屑砂岩等富含岩屑的砂岩,砂岩成分成熟度高,结构成熟中等;主要的储集空间为粒间溶孔、粒内溶孔和铸模孔,储层类型主要为孔隙型和裂缝-孔隙型,储层物性差,为典型的致密砂岩储层;压实作用和胶结作用是砂岩致密化的主要因素,而溶蚀作用和破裂作用是相对优质储层发育的关键;控制须四段相对优质储层形成的主要因素为沉积微相、埋藏早期和溶蚀期砂体所处的古构造位置以及(主要是下亚段)裂缝发育情况。据此建立了该区须四段储层预测地质模型:须四上亚段储层预测地质模型为三角洲前缘分流河道、河口坝微相+埋藏早期古构造高位置;须四段下亚段储层预测地质模型为砂岩含量高的辫状分流河道、河口坝微相+溶蚀期古构造高位置+裂缝发育区。A study is carried out on the controlling factors and geological prediction models in the 4th member of the Xujia- he Formation in Xiaoquan-Xinchang area, western Sichuan Basin. Technical methods or tools such as thin section observa- tion, SEM and cathodoluminescence spectroscope had been employed and data like reservoir physical parameters, sedi- mentary facies and so on had been utilized. The results show that the reservoirs in the formation are mainly sandstones with high lithic content, such as lithiarenite, sublitharenite and calcarenaceous sandstone. These sandstones have high compositional maturity and medium textural maturity. Reservoir space is mainly intergranular dissolved pore, intragranular dissolved pore and moldic pore. The reservoir are mainly of porous type and fractured-porous type with poor reservoir quality, and are typical tight sandstone reservoirs. Compaction and cementation caused densification of the sandstone while dissolution and fracturing played key roles in the formation of reservoirs with relatively good quality. Factor as depo- sitional microfacies, the position of sandstone in the Paleostructures during early burial process and dissolution period, and fracture growth （mainly at the lower section） are considered to control the formation of reservoirs with relatively good quality in the 4thmember of the Xujiahe Formation. Hence ,two geological prediction models are established for the upper and lower section of the 4th member respectively ： they are delta front distributary channel microfacies and/or mouth bar microfacies plus paleostrnctural high during early burial process, sandy braided distributary channel microfacies and/or mouth bar microfacies plus paleostructural high during dissolution period plus fracture zone.

关 键 词：成岩作用 储层特征 地质预测模型 须家河组 孝泉-新场地区 川西坳陷 

分 类 号：TE112.1[石油与天然气工程—油气勘探]