Diagenetic Aspects of the Nari Formation, Belab Nala & Kaura Sori Nala Sections, Sulaiman Province, Pakistan

Abstract

 Diagenesis of sandstones of the Nari Formation has been deduced from outcrop samples of Belab Nala & Kaura Sori Nala sections (Zindapir Anticlinorium, Sulaiman Province). Important diagenetic events are compaction & cementation. Effects of mechanical compaction are obvious & common as compared to chemical compaction evident by the severe deformation of carbonate rock fragments (CRFs) as well as shale rock fragments (SRFs). Silica, is present in insignificant quantity, is found to be the first cement whereas calcite, which is common, has been observed as late cement. Recrystallization and dolomitization are other diagenetic events registered during analysis. The results of present study reveal that sandstones of the Nari Formation could not have good reservoir potential for hydrocarbon in the studied area because of the ductile deformation of unstable lithoclasts and calcite cement which is main porosity occluding component.