Abstract

The Upper Jurassic Arab Reservoirs of UAE consist of a series of thinly bedded dolomite and limestone streaks of variable reservoir quality interbedded with impermeable anhydrite layers (Arab-A, B & C) and a more uniform coarsegrained oolitic/bioclastic limestone unit below (Upper Arab-D). A Multi-mineral Model (MULTIMIN) was prepared using Calcite, Dolomite, Illite and Anhydrite as the principal minerals. Reservoir Characterization was carried out for Two Wells, Well-A and Well-B and different Rock Types were identified for the Reservoir Modeling. Well-A is the Oil bearing well while Well-B is water bearing. Rock types in Arab formation are divided into 3 major rock type groups- Limestone, Dolomite and Anhydrite (based on the paper of Christophe,T. et al, SPE 117889). It has been observed from Poro-Perm data, that good reservoir quality is in dolomites. Permeability transforms are generated for each rock type in Arab formations in Well-A. Saturation model in Arab formation is based on porosity saturation transforms for each zone- Arab A, Arab B & Arab C and their sub units. As no transition seen from log signature in saturation, a height function is not attempted. Good match seen between log saturation and PHI-SW transform derived saturation. Computed Water Saturations and Permeability for each Petrophysical Rock Types (PRT) were eventually used for the Reservoir Modeling