Geothermal reservoir assessment based on slim hole drilling. Volume 2: Application in Hawaii: Final report

Technical Report · Wed Dec 01 04:00:00 EST 1993

OSTI ID:10116765

Olson, H J ^[1]

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1. Hawaii Natural Energy Inst., Honolulu, HI (US)

The Hawaii Scientific Observation Hole (SOH) program was planned, funded, and initiated in 1988 by the Hawaii Natural Energy Institute, an institute within the School of Ocean and Earth Science and Technology, at the University of Hawaii at Manoa. Initial funding for the SOH program was $3.25 million supplied by the State of Hawaii to drill six, 4,000 foot scientific observation holes on Maui and the Big Island of Hawaii to confirm and stimulate geothermal resource development in Hawaii. After a lengthy permitting process, three SOHs, totaling 18,890 feet of mostly core drilling were finally drilled along the Kilauea East Rift Zone (KERZ) in the Puna district on the Big Island. The SOH program was highly successful in meeting the highly restrictive permitting conditions imposed on the program, and in developing slim hole drilling techniques, establishing subsurface geological conditions, and initiating an assessment and characterization of the geothermal resources potential of Hawaii - - even though permitting specifically prohibited pumping or flowing the holes to obtain data of subsurface fluid conditions. The first hole, SOH-4, reached a depth of 2,000 meters, recorded a/bottom hole temperature of 306.1 C, and established subsurface thermal continuity along the KERZ between the HGP-A and the True/Mid-Pacific Geothermal Venture wells. Although evidence of fossil reservoir conditions were encountered, no zones with obvious reservoir potential were found. The second hole SOH-1, was drilled to a depth of 1,684 meters, recorded a bottom hole temperature of 206.1 C, effectively doubled the size of the Hawaii Geothermal Project-Abbott/Puna Geothermal Venture (HGP-A/PGV) proven/probable reservoir, and defined the northern limit of the HGP-A/PGV reservoir. The final hole, SOH-2, was drilled to a depth of 2,073 meters, recorded a bottom hole temperature of 350.5 C, and has sufficient indicated permeability to be designated as a potential discovery.

• Research Organization: Electric Power Research Inst., Palo Alto, CA (US); Hawaii Natural Energy Inst., Honolulu, HI (US); GeothermEx, Inc., Richmond, CA (US)
• Sponsoring Organization: Electric Power Research Inst., Palo Alto, CA (US)
• OSTI ID: 10116765
• Report Number(s): EPRI-TR--103399-V2; ON: UN94005625
• Country of Publication: United States
• Language: English

Related Subjects

15 GEOTHERMAL ENERGY
150303
BOREHOLES
DRILLING
EDUCATIONAL FACILITIES
EXPLORATORY DRILLING AND WELL LOGGING
EXPLORATORY WELLS
GEOTHERMAL RESOURCES
GEOTHERMAL WELLS
HAWAII
PERMEABILITY
PUMPING
RESOURCE ASSESSMENT
RIFT ZONES
WELL DRILLING