3D Facies Modeling of Mishrif Reservoir in Halfaya Oil Field

Abstract

This research deals with the study of the types and distribution of petrographic microfacies and Paleoenvironments of Mishrif Formation in Halfaya oil field, to define specific sedimentary environments. These environments were identified by microscopic examination of 35 thin sections of cutting samples for well HF-9H as well as 150 thin sections of core and cutting samples for well HF-I. Depending on log interpretation of wells HF-1, HF-316, HF-109, IIF-115, and IIF-272, the sedimentary facies were traced vertically through the use of various logs by Petrel 2013 software in addition to previous studies. Microfacies analysis showed the occurrence of six main Paleoenvironments within Mishrif succession, represented by basin, slope, shoal, Rudist biostrome, back shoal, and lagoon. Mishrif Formation was divided into six reservoir units depending on well logs and CPI. These units are separated by low porosity and high-water saturation of barrier beds. The reservoir beds from top to bottom are MA, MB1, MB2, MCI, and MC2. The reservoir units MB1, MB2, and MCI are the most important in the field of interest due to good reservoir properties and being the principle oil-bearing units in Mishrif Formation.

Petrophysical Evaluation of Mishrif Formation Using Well Logging in North Nasiriya Oil Field

“…Based on [15] study, the main reservoir unit of the Mishrif Formation is MB1. [16] subdivided the Mishrif Formation in the Halfaya oil field into five teams and mentioned that the MB1 and MB2 are the most important units in the formation as main oil-bearing units due to the good reservoir properties…”

Microfacies and Diageneses Associated Mishrif Formation in X Oilfield Southeast Iraq

“…Within the Mishrif succession, microfacies study revealed the presence of six major Paleoenvironments: basin, slope, shoal, Rudist biostrome, rear shoal and lagoon (Nasser, 2021).It is the continuous deposition of shallow marine carbonates. Iraq's most prolific period contains over 80% of the country's oil reserves.…”