鄂尔多斯盆地西峰油田长8储层的砂岩成岩作用

根据砂岩薄片、铸体薄片、扫描电镜、X-衍射等分析,对西峰油田长8储层砂体的岩石学特征、成岩作用进行研究.研究表明:该区长8储层砂体成分主要以长石岩屑砂岩为主.储层砂岩的成岩处于晚成岩A期,早期的压实作用、多种矿物胶结作用是使物性变差的两个重要成岩作用,而溶蚀作用,特别是长石的溶蚀是储层物性变好的重要成岩控制因素.

Sandstone diagenesis of Chang-8 reservoir in Xifeng Oilfield of Ordos Basin

Based on the analysis of casting lamella, scan electron microscope and X-ray diffractions, this article researched into the characteristics of petrology and diagenesis on Chang-8 reservoir in Xifeng Oilfield of Ordos Basin. The study result showed that the main sandstone in the area is feldspathic litharenite with low compositional maturity. The diagenetic characteristics of Chang-8 sandston show that this set of sandstones are in the early period of the late diagenetic stage at present. The early diagenetic compaction and multi-mineral cementation are major effective factors that lead to poor petrophysical property of Chang-8 reservoir, while dissolution, in particular dissolution of feldspar, is one of significant factors controlling the quality of the reservoir.