Improved Methodology for Determining Total Gas Content. Volume 1. Canister GasDesorption Data Summary. Topical Report, September 1-November 15, 1993

摘要

The report, Volume I of a series, is a technical reference of the variousnumerical techniques commonly used in the natural gas industry for analyzing coal drill core and cuttings canister gas desorption data. Exploration geologists and reservoir engineers use the results obtained from these analyses to estimate the gas content of coal seam gas reservoirs. The report documents nine technical data bases containing benchmark reservoir gas content values and drill core/cuttings canister gas desorption data sets for coal seam gas wells located in the San Juan Basin of Colorado and New Mexico and the Piceance Basin of Colorado. The report also provides: (1) background information on the technical basis of commonly used numerical techniques; (2) descriptions of methods used for acquiring and analyzing canister gas desorption data; and (3) case study analyses of the expected magnitude of error associated with the use of different procedures for estimating coal seam reservoir gas content values. The case studies analysis results indicate that estimated gas content values may be biased due to the shortcomings of the sample type and collection methodology, gas desorption testing conditions, and the numerical technique used for the data analysis.