The Role of the Geologist in the Assessment ofCoalgas Accumulations

摘要

Finding and exploiting coalgas accumulations requires thesimultaneous application of accurate geological interpretationsand effective engineering technology. This linkage is wellestablished in conventional gas systems where reservoirs arelocalized features having discrete boundaries. Coalgasaccumulations, however, are often regional in extent and lackobvious seals or traps. As a result, the geological factorscontrolling gas-in-place and production rates can be difficult toidentify and quantify. This can lead to the erroneousassumption that the reservoir is too complicated tocharacterize, or that heterogeneities are uniformly distributedand can be approximated with simple models.Many companies emphasize engineering over geology in theexploration and development of coalgas accumulations. Thismakes little sense, especially for marginally economic projectsthat cannot sustain the high cost of trial-and-error drilling.Nonetheless, basic geological data and analysis are oftenexcluded from the project budget as a low priority item. Tochange this, geologists must do a better job of defining theirresponsibilities, demonstrating why geological knowledge is so important, and delivering recommendations that will favorablyimpact the bottom line.