| Abstract |
Shell has drilled one dry hole and one commercial discovery in The Geysers area of northern California. The dry hole was hot ( 2 447?F) but failed to encounter fractures necessary for commercial steam recovery. The discovery producer, located one and one-half miles south of The Geysers field, encountered dry steam flowing at rates of about 200,000 lb/hr. A confirmation well is currently being drilled. Temperature gradients range from 2-4"F/100 ft. above 3,000 ft. and from 6-8"F/100 ft. from 3,000 ft. to the steam reservoir. The reservoir temperature (+465"F) and pressure (2500 psia) are typical of The Geysers area. Local concentrations of hydrogen sulfide in excess of 3,000 ppm were encountered in one well. Shell started acquiring acreage in 1971, and now holds 15,000 acres (Fig. 1 ). Two Federal leases, U.S. One (2477 acres) and U.S. Two (1600 acres) were acquired in January 1974 in the first Federal geothermal competitive lease sale. |