鄂尔多斯盆地姬塬地区长2油层组成岩作用研究  

The diagenesis of Chang 2 formation in Jiyuan Area Ordos Basin

作　　者：刘晓娟[1] 林艳波[2] 范正平[2] 

机构地区：[1]西安石油大学石油工程学院,陕西西安710065 [2]中国石油天然气股份有限公司长庆油田分公司,陕西西安710021

出　　处：《西北大学学报（自然科学版）》2011年第5期857-862,F0003,共7页Journal of Northwest University（Natural Science Edition）

基　　金：国家科技重大专项课题基金资助项目(2008ZX05013-002)

摘　　要：目的探讨姬塬地区长2油层组成岩作用对储层的影响。方法通过普通薄片、铸体薄片、扫描电镜、X衍射对储层进行系统研究。结果姬塬地区长2储层埋藏过程经历了6个成岩阶段,发生了5种成岩作用(压实、胶结、溶蚀、交代和破裂)和4期溶蚀事件(同生期酸性溶蚀、抬升剥蚀期酸性溶蚀、浅埋藏期碱性溶蚀和深埋藏期酸性溶蚀),现今处于晚成岩A期,以次生溶蚀孔隙为主。结论对研究区储层影响最重要的是浅埋期的碱性溶蚀和深埋藏期酸性溶蚀;浅埋期主要是火山物质等发生水解溶蚀形成了可观的溶蚀孔隙,而深埋阶段则以长石、岩屑颗粒的酸性溶蚀为特征。Aim To ascertain the effect of diagenesis on reservoirs quality of the Chang 2 sandstone in Jiyuan Area.Methods The data analysis was done on thin section,cast section,SEM and Xray diffraction.Results It has undergone 6 diagenetic stages,5 key types of diagenesis and 4 dissolution phases.The key diagenesis includs compaction,cementation,dissolution,alternation and fracture.The 4 dissolution phases is as follows： acidic dissolution in syngenesis,acidic dissolution during uplift,alkalic dissolution in eogenetic stage and acidic dissolution during late diagenesis.Conclusion The last two dissolution are more important.The volcanics in the sandstone was hydrolyzed and dissoluted during alkalic dissolution in eogenetic stage,and it yields considerable secondary porosity and chorite.The feldspar grains or fragments were dissolved by the organic acid water and also formed lots of secondary pores during late diagenesis.

关 键 词：成岩作用 碱性溶蚀 火山物质 绿泥石 次生孔隙 

分 类 号：TE21[石油与天然气工程—油气井工程]