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Title: Monitoring the Bulalo geothermal reservoir, Philippines, using precision gravity data

Journal Article · · Geothermics
 [1];  [2]
  1. Philippine Geothermal, Inc., Pasay City (Philippines)
  2. Unocal Geothermal, Santa Rosa, CA (United States)

Precision gravity monitoring of the Bulalo geothermal field began in 1980 to estimate the natural mass recharge to the reservoir. Between 1980 and 1991, gravity decreases exceeding 2.5 {times} 10{sup {minus}6} N/kg (250 microgals) were observed in response to fluid withdrawals. A maximum rate of {minus}26 microgals per year was observed near the production center. Mass discharges predicted by recent reservoir simulation modeling generally match those inferred from the observed gravity data. According to simulation studies, no recharge occurred between 1980 and 1984. The mass recharge between 1984 and 1991 was estimated to be 30% of net fluid withdrawal during the same period, equivalent to an average rate of 175 kg/s (630 metric tons per hour).

OSTI ID:
143816
Journal Information:
Geothermics, Vol. 22, Issue 5-6; Other Information: PBD: Oct-Dec 1993
Country of Publication:
United States
Language:
English