The study area is in the Indian Basin Field, Upper Pennsylvanian Cisco/Canyon Formations in Southeastern New Mexico. The reservoir is composed of an algal mound, facies complex including boundstone, fusulinid grainstone-wackstone, and crinoidal grainstone-packsone. All reservoir facies have undergone multiple phases of dolomitization that have created vuggy and intercrystalline porosity. Wells that have been completed in the vuggy intervals typically have the highest production of oil and gas.
This study involves a data set which includes both core and logs. The core is approximately 300 ft. (91.4m) of vuggy and non-vuggy dolomite. Full diameter core analysis was performed. Log control includes: nuclear magnetic resonance (3 runs), electrical borehole images, neutron, density, sonic, spectral gamma ray, induction, and resistivity.
The purpose of this project is to quantify vuggy porosity in carbonates using borehole image logs calibrated to digital core images. Another aspect of this study is to compare pore-size distributions from digital images of core to nuclear magnetic resonance (NMR) imaging logs. NMR logs are sensitive to fluid content and pore-size distribution. However, their behavior is not well understood in carbonate reservoirs.
AAPG Search and Discovery Article #90925©1999 AAPG Foundation Grants-in-Aid