An Integrated Approach to Determine Flow Units in a Complex Jurassic Carbonate “Marrat” Reservoir in Burgan Oil Field, Kuwait

Muktibrata Bhattacharya*, Mishari Najem Al-Qattan, and Reham Ali Al-Houti
KOC
*[email protected]

The carbonates of the Marrat Formation in the Magwa area of Kuwait’s Greater Burgan oil field were deposited in a shoal lagoonal complex, essentially in a ramp-to-rim environment. An inferred highstand systems tract holds substantial oil reserves in the middle Marrat reservoirs. The upper and lower Marrat are argillaceous with poor reservoir characteristics. This reservoir starting producing in 1984 and its depletion was driven with very little aquifer support. However, because asphaltene flocculation with pressure drop inhibit smooth production, a water-injection program is planned. It is therefore critical to understand the reservoir geology and flow units in order implement the program. An integrated approach was adopted which included: (1) rock-type transforms to quantifiable petrophysical based flow units; (2) sequence stratigraphic framework; and (3) laboratory-derived continuous porosity and permeability data from a well. The study established three flow units within the reservoirs. The graphical tools used to determine the flow units were: (1) Winlands porosity-permeability cross-plot, (2) stratigraphic flow profile, (3) stratigraphic modified Lorenz plot, and (4) cumulative flow and storage capacity. This well-proven methodology for identifying flow units will provide the basis for the water injection and perforation strategy and will influence the future business decision strategy for a successful water-flooding program.

AAPG Search and Discovery Article #90077©2008 GEO 2008 Middle East Conference and Exhibition, Manama, Bahrain