Microfacies Analysis and Diagenesis Processes Development for Khasib Formation of East Baghdad Oil field, Iraq

Abstract

Khasib Formation was studied in East Baghdad oilfield, Al-Rashdiya area in Baghdad
Governorate. The lithology of the formation is limestone throughout the whole sequence in all
studied wells (EB-83, EB-87, EB-92, and B94). It is bounded conformably from the top with
Tanuma Formation and lower contact with Kifl Formation. The petrographic study shows three
main microfacies (lime mudstone, non-laminated peloidal pack-grainstone, and laminated
peloidal grainstone) and two submicrofacies (homogeneous non-fossiliferous lime mudstone,
bioclast lime mudstone) the study shows the abundance of non-skeletal agains skeletal grains.
All microfacies indicate facies zone (7, 8, and 9A) which reflect the platform interior between
the open marine to the restricted and evaporitic or brackish water depositional environment.
Several diagenesis processes have been distinguished that affected the texture and porosity of
Khasib Formation, the most important of which were dissolution, cementation, dolomitization,
compaction, micritization, and the porosity of a non-fabric selective type.