Reconciliation of Pc-Derived and Elogs-Derived Water Saturation on the Al Khalij Field - Offshore Qatar

B. Lalanne¹, R. Boichard¹, C. Maza¹, M. Rebelle¹, and N. Bounoua²

Abstract

The Al Khalij oil field, located offshore Qatar, has been discovered in 1991 and put into production in 1997 from several carbonate reservoirs trapped within a stratigraphic closure.

One particularity of the oil bearing section is that it consists of an alternation of metric layers with quite distinct capillary properties. This results in a vertical water saturation profile with strong Sw variations between layers, particularly emphasized by the fact that most reservoirs lie within the capillary transition zone. As indicated by both Elogs and Pc data, the Sw contrast can thus reach 40 to 70 saturation units between adjacent layers, sometimes - and it's quite remarkable - with hardly noticeable vertical porosity PHI variations.

AAPG Search and Discovery Article #90188 ©GEO-2014, 11th Middle East Geosciences Conference and Exhibition, 10-12 March 2014, Manama, Bahrain