Evaluation of Granite and Carbonate Wash Reservoirs and Determination of Relative Producibility
The complex formations of north Texas and western Oklahoma present two individual challenges in defining hydrocarbon reservoirs. The first being in the deeper Carbonate Wash intervals where productive zones are defined by identifying and quantifying vugular porosity systems that are not always apparent on standard triple combo log data. Comparisons will be made with high-resolution micro-resistivity images to confirm the rock texture. The second challenge exists within the shallower more siliceous Granite Wash interval where the complex mineralogy make defining porosity, grain density and clay volume extremely difficult. This presentation will describe techniques used to address these challenges utilizing Nuclear Magnetic Resonance and Geochemical logging measurements. We also consider the efficiency of the data acquisition process to minimize rig time and maximize the ability to sufficiently evaluate all possible hydrocarbon bearing intervals.. The presentation will also discuss the computation of relative permeability in order to estimate fluid contribution taking into account the irreducible fluid volumes measured by the Magnetic Resonance tool.
AAPG Search and Discover Article #90065©2007 AAPG Southwest Section Meeting, Wichita Falls, Texas