Exploration and Development History
Biliran Island lies immediately to the north of Leyte, alongside the active Philippines Fault. In 1979-1980, geothermal exploration started in Biliran with the inventory of surface hydrothermal features and geological reconnaissance by PNOC-EDC and KRTA.
- 1979 – 1980 – Geoscientific studies (EDC/KRTA)
Geophysical surveys were conducted between 1980 to 1981 including Schlumberger resistivity traversing (SRT), vertical electrical sounding (VES), and dipole-dipole resistivity survey (DRS). In 1981, DSIR reviewed all surface exploration work done in Biliran as part of New Zealand-Philippines Energy Cooperation Program.
- 1981 – 1982 – Exploration Drilling
- BN-1 = neutral-CI w/ T = 250°C (low WHP, did not discharge)
- BN-2 = neutral-C1 w/ T = 210°C (failed to sustain discharge due to mineral scaling)
- BN-3 = acid CI-SO4, pH 3 at weirbox, T = 330°C (cement plugged due to corrosion)
Based on these studies, three prospective targets were delineated, namely: Vulcan, Kalambis and Panamao areas.
Among these three, Vulcan area was judged most impressive because of its close association with solfataric activiry. In
1982, three exploration wells (BN-1, BN-2, and BN-3) were drilled to test the geothermal potential of Vulcan Area.
- 1991 – 1993 Additional geoscientific studies (PNOC-EDC)
- Geology Survey
- Geochemical sampling
- Resistivity (VES)
- 2004 DOE looking for investor
- 2007 DOE offers Biliran for bidding
- 2008 Geothermal Service Contract awarded to Biliran Geothermal, Inc. (BGI)
- Additional Surface Exploration
- MT Survey
- Water/Gas resampling
- Detailed Structural Mapping
- 2013 to present Confirmatory Drilling
Biliran Geothermal Gallery
Apuada, N.A. (1992): The Resistivity Signature of Biliran
Island. PNOC-EDC Internal Report. Makati,
KRTA (1986): Evaluation of the Biliran Geothermal
Prospect. PNOC-EDC Internal Report. Makati,
Ramos-Candelaria and Baltasar, A.S.J (1993): Geochemical
and Isotopic Investigation of Biliran Geothermal
Discharges. PNOC-EDC Internal Report. Makati,
Pagado, E.S., Camit, G.R.A and Rosell, J.B (1993): The
Geology and Geothermal Systems of Biliran Island.
PNOC-EDC Internal Report. Makati, Philippines.
Department of Energy (DOE)
Photos by Jalmz