1. Review of the results presented in WGC2005 concerning the investigation of Enhanced Geothermal Systems by D. Mendrinos and Dr. C. Karytsas Centre for Renewable Energy Sources February 2006

2. Geophysical Investigation Hydrothermal Systems Hydrothermal Systems  Enhanced Geothermal Systems  Enhanced Geothermal Systems

3. Exploration Resistivity Resistivity  21 papers Heat Flow Heat Flow  10 papers Gravity Gravity  2 papers Reflection Seismics Reflection Seismics  2 papers Porosity Porosity  2 papers

4. Rocks Resistivity DC resistivity (Schlumberger, etc.) DC resistivity (Schlumberger, etc.)  1-D Inversion  1-D Inversion (2 papers)  3-D Inversion  3-D Inversion (3 papers) Magneto-Telluric (MT) Magneto-Telluric (MT)  1-D Inversion  1-D Inversion (6 papers)  2-D Inversion  2-D Inversion (5 papers)  3-D Inversion  3-D Inversion (4 papers)  CSMT  1-D Inversion  CSMT  1-D Inversion (1 paper) Core-Sampling Core-Sampling  laboratory measurements  laboratory measurements (1 paper)

5. Earth Heat Flow Borehole Temperature Borehole Temperature  4 papers Thermal Manifestations Flow Rate Thermal Manifestations Flow Rate  3 papers Earthquakes Earthquakes  2 papers Airborne Gamma Ray Airborne Gamma Ray  1 papers Airborne Magnetic Airborne Magnetic  1 papers

6. Production Micro-Seismic Activity Micro-Seismic Activity  4 papers Micro-Gravity Transients Micro-Gravity Transients  3 papers Temperature Transients Temperature Transients  1 paper SP Transients SP Transients   1 paper

7. PNOC Experience, Philippines Period: 1979-1995 Schlumberger Resistivity Schlumberger Resistivity  shallow current penetration  smectite cap-rock (~10 Ohm.m)  manifestations of deeper reservoirs  1000 MWe

8. PNOC Experience, Philippines Period: 1995-2005 MT, 1-D Inversion MT, 1-D Inversion  deeper current penetration ( 2 km)  geothermal reservoir (50-100 Ohm.m)  enhanced geothermal systems  2000 MWe

10. ENEL Experience, Italy Reflection Seismics Reflection Seismics  Major fault zones  ~ 4 km depth  700 MWe

11. MT, 3-D Inversion Excellent imaging down to 2-3 km Excellent imaging down to 2-3 km  Need for noise filtering at low frequencies Sophisticated algorithms Sophisticated algorithms  Demanding computing equipment Interpretation: Interpretation:  Better starting point for the Earth Scientist  Correlation with drilling & other data