摘要
根据砂岩普遍薄片、铸体薄片、扫描电镜和其他化验资料等,系统研究柴达木盆地北缘地区鄂博梁Ⅲ号构造的岩石学特征、成岩作用及对孔隙的影响.结果表明:研究区储集砂岩较细,以细砂岩和粉砂岩为主,含少量中砂岩和粗砂岩;岩石类型主要为长石砂岩和岩屑长石砂岩,含少量长石岩屑砂岩.成岩作用主要为压实作用、胶结作用和溶蚀作用,成岩作用阶段已经达到晚成岩阶段A期.压实作用中等是孔隙度大量丧失的主要原因.胶结作用较强,胶结物主要有碳酸盐胶结物、硫酸盐胶结物、硅质胶结和黏土矿物胶结,胶结物充填孔隙、堵塞喉道,在成岩早期能起骨架支撑缓解压实作用的进行.溶蚀作用中等,主要为长石、岩屑、碳酸盐胶结物及杂基等易溶组分溶蚀成粒间、粒内溶蚀孔,为储层增加次生孔隙,属于建设性成岩作用.
Based on cast thin section,scanning electron microscopy and laboratory data,a systematic study was conducted on petrology and diagenesis and their effect on the porosity of the reservoir in No.Ⅲstructure of Eboliang area,Qaidam basin.The results show that the study area is of mainly fine sandstone and siltstone, the reservoir granularity is small,the rock types are mainly arkose and lithic arkose with little feldspathic lithic sandstone.The sandstones have suffered from various kinds of diagenesis,such as compaction,cementation and dissolution,reaching the A period of the late diagenetic stage.Compaction effect,of medium degree,mostly accounts for the reduction of prosity.Cementation,being strong,consists of carbonate cement,sulphate cement, siliceous cement and clay mineral.The cements All up the pore space and block up the throat,but they can resist the running of compaction in the early diagenetic stage.Dissolution is of medium degree and feldspar, debris and carbonate cements have dissolved into the emposieu.Belonging to constructive diagenesis,dissolution increases the secondary porosity.
出处
《兰州大学学报（自然科学版）》
CAS
CSCD
北大核心
2012年第6期1-7,共7页
Journal of Lanzhou University(Natural Sciences)
基金
国家重点基础研究发展计划(973计划)项目(2011CB201104)
中国科学院油气资源研究重点实验室开放基金项目(KFJJ2012-05)
关键词
储层物性
控制因素
上、下油砂山组
鄂博梁地区
reservoir property
controlling factor
lower-upper Youshashan formation
Eboliang area
