定边地区富县组储层砂岩成岩作用及孔隙演化特征  

Diagenesis and Porosity Evolution of Fuxian Formation Sandstone Reservoir in Dingbian Area of Ordos Basin

作　　者：唐波[1] 陈义才[1] 林杭杰[1] 赵鹤森[1] 张雁[2] 刘玉峰[2] 

机构地区：[1]成都理工大学能源学院,四川成都610059 [2]长庆油田采油三厂,宁夏银川750006

出　　处：《襄樊学院学报》2011年第5期37-41,共5页Journal of Xiangfan University

基　　金：国家青年基金项目(40602012)

摘　　要：通过岩心观察、常规薄片、铸体薄片、扫描电镜以及化验等手段对鄂尔多斯盆地定边地区富县组砂岩的成岩作用、孔隙演化进行了分析研究.富县组储层砂岩主要为含砾粗砂岩、粗砂岩,该储层砂岩经历的主要成岩作用有压实-压溶作用、胶结作用、溶蚀作用、破裂作用等.根据地史恢复和成岩特征综合分析,该地区富县组砂岩目前处于晚成岩A期阶段.储层砂岩成岩过程中,压实-压溶作用对储层的孔隙度影响最大,压实-压溶作用使得储层原始孔隙度减少约25%,孔隙度损失率达68%;胶结作用使储层的孔隙度降低了3%,孔隙度损失率7%;晚侏罗世-早白垩世发生的溶蚀作用对改善储层的孔渗性能起到了非常大的作用,使孔隙度由11%升高17%;晚白垩世以来,随着上覆地层的剥蚀,富县组埋深有所降低,晚期胶结作用使孔隙度缓慢降低到16%左右.Through the observation of core, thin-section, casting thin-section, SEM analysis and chemical test, diagenesis, and porosity evolution of sandstone reservoir of Dingbian area in Ordos Basin are studied. The sandstone mainly contains conglomeratic sand, grit stone in this region. Researches show that the diagensis of reservoir sandstone of Fuxian formation mainly experienced is compaction＆ pressure-solution, dissolution, cementation, catastasis, etc. According to comprehensive analysis of buried history＇s recovery and diagenesis, sandstone of Fuxian Formation is now in the A stage of later diagenesis. During the process of rock-forming, the compaction ＆pressure-solution reservoir porosity makes original porosity of reservoir reduced by 25%,and 68% original porosity has been lost. Cementation makes reservoir porosity 3% reduced, and 7% original porosity has been lost. Dissolution has played a critical factor in improving sandstone＇s physical property and porosity has increased from 11% to 17% in the Late Jurassic-Early Crataceous ; Late Cementation makes porosity slowly decrease to 16 when overlying formation has been denuded and depth of burial of Fuxian Formation decreased since Late Cretaceous.

关 键 词：富县组 成岩作用 孔隙演化 定边地区 鄂尔多斯盆地 

分 类 号：TE122.1[石油与天然气工程—油气勘探]