Completion Techniques for Geothermal-Geopressured Wells. Final report

Geological studies have established that geothermal-geopressured formations can be found at depths of 10,000 to 18,000 feet in the Gulf Coast area of Texas and Louisiana. Bottom hole pressures are in the range of 9,000 to 15,000 psig and temperatures 250-350 F. Test wells to tap these reservoirs can be drilled routinely, utilizing available equipment and methods. Electric logs, surveys, cores and production tests can be used to assess these resources and to evaluate their economic viability as primary sources of energy. But it will be necessary to complete the wells in such fashion that production of the high-pressured fluid can be obtained to deliver heat, mechanical energy and methane gas in economic quantities. This will require carefully considered completion techniques, involving pipe sizes and accessory equipment suitable for high volumes of fluid. Completion operations may include formation stimulation treatments and/or sand control measures to obtain optimum rates of flow with minimum sand influx. It appears that gravel-packed completions will be more feasible at this time than chemical consolidation treatments to control sand production because of high temperatures, thick producing intervals, and high-velocity flow rates. Flow rates up to 100 barrels per day per foot of perforations should be possible from consolidated formations without sand control treatments