Microfacies and paleoenvironment of the Mishrif Formation (middle Cenomanian–early Turonian), in Nasiriyah oil field in Southern Iraq

The Microfacies analysis of the Cretaceous Mishrif Formation was studied in Nasiriyah oil field Governorate, southern Iraq using integrated borehole data set that included, core samples and well logs newly drilled to analyze microfacies Diagenesis Process formation, 100 thin sections for selected well. results show formation composed of: (top base) a fine-grained, limonitic fresh water limestone containing Charophytae. Four facies’ associations were distinguished Formation. These include: - Restricted shallow Open Marin environment is represented by Wackstone Mudstone Wackstone. open marine bioclastic wackestone packestone, as rudistid floastone rare situations. Shoal Environmentis packstone grainstone, rudstone. Deep Marine mudstone packstone. six diagenetic processes affected on Formation: Cementation, Micritization, Recrystallization, Dissolution, Compaction Pressure Solution (Stylolization), Dolomitization, found sections.