Microfacies and depositional environment of the Upper Oligocene and Lower Miocene successions from Iraqi Kurdistan Region

Abstract

Upper Oligocene and Lower Miocene successions in the High/Low Folded Thrust Zones boundary from the Sulaimani District, Kurdistan region, northeast Iraq, are manifested and represented by Bajwan, Anah and Jeribe formations, which are consists mainly of carbonates. Studied sections mostly underlain by unconformity, above the Eocene carbonates (Pila Spi Formation) and overlain unconformably by the Middle Miocene deposits of Fath-a (Lower Fars) Formation. Three studied sections (Basara, Xamsha and Wazyara) have been analyzed for their microfacies and depositional environments. Accordingly, eleven microfacies are identified and analyzed. Main depositional environments are represented by the middle ramp setting that is changed to reef depositional environment during the Upper Oligocene (Bajwan Formation), while inner ramp setting that is changed to semi-closed as lagoonal environment during the Lower Miocene(Anah and/ or Jeribe formations). Keywords: Upper Oligocene, Lower Miocene, Microfacies, Depositional environment, Kurdistan.

Keywords

• Upper Oligocene
• Lower Miocene
• Microfacies
• Depositional environment
• Kurdistan.