Petrographical and microfacies study of jeribe formation (m. miocene) in Ashdagh mountain, Kurdistan region, Iraq

This study deals with the Middle Miocene Jeribe Formation in the Ashdagh Anticline in Darzila Village near Sangaw in Sulaimani Governorate, Iraq. Stratigraphic analysis has shown that Jeribe Formation consists of recrystallized and dolomitized, mostly limestone which, as a whole, supported its reservoir potential. Petrography has provided a diversity of fauna such as large benthic foraminifera, Astrotrillina sp., Miliolid in addition to Borelis melo curdica, which for a long time has been considered an index fossil for this formation. Other fauna includs several types of mollusks. The Jeribe carbonates were subjected to various diagenetic processes ranging from micritization, dolomitization, cementation, compaction, dissolution, and others. The formation consists of three major limestone microfacies: mudstone, wackestone, and packstone/ grainstone. The evidence from petrography and facies analysis support that the Jeribe Formation was deposited in restricted marine environment.