Print this pageExtracting Maximum Petrophysical and Geological Information from Limited Database: A Case Study From Sulimar Queen Field, New Mexico
ALI, MAQSOOD, ADWAIT CHAWATHE, AHMED OUENES, W. W. WEISS, and MARTHA CATHER
The characterization of old fields lacking sufficient core material and modern log suites is a very difficult task. A methodology was developed to improve the quality and quantity of the data collected from old gamma ray and neutron logs, one core, core reports from two wells, and four modern log suites for improved reservoir characterization of the Sulimar Queen. All logs were digitized at 0.5 feet interval.
Initially using a minipermeameter, permeability measurements were made on a fine grid, and four alternating high and low permeability zones were recognized. To map these zones, correlations were developed between gamma ray core porosity, permeability, and water saturation. The old gamma ray logs were first rescaled/calibrated for consistency and reliability based on the modern logs. The porosity obtained using the rescaled gamma ray logs captured the presence of four zones which were not distinguishable in the old gamma ray logs before rescaling.
Because of the fine sampling grid and small area of investigation of the minipermeameter probe, each thin section contained 10 permeability points. A large set of petrographic data directly related to permeability was collected using few thin sections. The effects of each petrographic element on permeability was established using regression analysis and a newly developed fuzzy logic algorithm.
A detailed geologic model was constructed on the basis of the information obtained from cores and rescaled gamma ray logs which is in agreement with the production data, and hence also improved the reservoir simulation results.