Sedimentary and Tectonic, Implications on Late Cretaceous Reservoir Succession Along the Oil Fields, Mosul Block, Northwestern Iraq

Abstract

This study focuses on Cretaceous reservoir succession development and evaluated in the Mosul Block NW Iraq. The oil fields are Sufayia, Ain Zalah, and Tel-Hajer (Sufayia-1, Ain Zalah-29, producing fields and Exploration well Tel-Hajar-1 South of Jabal Sinjar-non producing field). The Mosul Block in Northwestern Iraq has Cretaceous reservoirs, but less research has been done on the deeper plays of the Lower Cretaceous, Jurassic, and older reservoirs. Non-Tertiary reservoirs in this zone are unlike what exists in eastern Iraq. The reservoir facies and Stratigraphy evolution are influenced by three tectonic development phases: Phase I (Late Albian to Cenomanian): The Gir Bir Formation The main reservoir exhibits good hydrocarbon efficiency reservoir, characterized by Shoal Rudist and benthic foraminifers. Notably, this formation is absent in Tel-Hajar. Phase II (Turonian to Late Campanian, obduction phase): Tel-Hajar structure South Jabal Sinjar, as positive region (Austrian orogeny) which uplifts the Wajnah Formation Sub basinal, Facies overlying the Mushorah Formation in Ain Zalah and Sufayia fields. Phase III (Late Campanian to Maastrichtian), fractured basinal facies Shiranish Formation reservoir, located in the northern parts of Mosul Block Ain Zalah and Sufayia fields. However, no reservoir of cretaceous of Tel Hajar-1. The study concludes that the oil fields northwest of Mosul Blocks (Sufayia and Ain-Zalah fields) have good potential produced from the Cretaceous reservoir, while the south of Mosul Blocks well (Tel-Hajer -1) has weak potential as cut-out cretaceous stratigraphy (pale high) Cretaceous stage.