Review of the results presentedReview of the results presentedin WGC2005in WGC2005

concerning the investigation ofconcerning the investigation ofEnhanced Geothermal SystemsEnhanced Geothermal Systems

by by D. Mendrinos and Dr. C. KarytsasD. Mendrinos and Dr. C. Karytsas

Centre for Renewable Energy SourcesCentre for Renewable Energy Sources

February 2006February 2006

Geophysical InvestigationGeophysical Investigation

Hydrothermal SystemsHydrothermal Systems

Enhanced Geothermal SystemsEnhanced Geothermal Systems

ExplorationExploration

ResistivityResistivity 21 papers

Heat FlowHeat Flow 10 papers

GravityGravity 2 papers

Reflection SeismicsReflection Seismics 2 papers

PorosityPorosity 2 papers

Rocks ResistivityRocks 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 CSMT 1-D Inversion 1-D Inversion (1 paper)

Core-SamplingCore-Sampling laboratory measurements laboratory measurements (1 paper)

Earth Heat FlowEarth Heat Flow

Borehole TemperatureBorehole Temperature 4 papers

Thermal Manifestations Flow RateThermal Manifestations Flow Rate 3 papers

EarthquakesEarthquakes 2 papers

Airborne Gamma RayAirborne Gamma Ray 1 papers

Airborne MagneticAirborne Magnetic 1 papers

ProductionProduction

Micro-Seismic ActivityMicro-Seismic Activity 4 papers

Micro-Gravity TransientsMicro-Gravity Transients 3 papers

Temperature TransientsTemperature Transients 1 paper

SP TransientsSP Transients 1 paper

PNOC Experience, Philippines PNOC Experience, Philippines Period: 1979-1995 Period: 1979-1995

Schlumberger ResistivitySchlumberger Resistivity

shallow current penetration

smectite cap-rock (~10 Ohm.m)

manifestations of deeper reservoirs

1000 MWe

PNOC Experience, Philippines PNOC Experience, Philippines Period: 1995-2005Period: 1995-2005

MT, 1-D InversionMT, 1-D Inversion

deeper current penetration ( 2 km)

geothermal reservoir (50-100 Ohm.m)

enhanced geothermal systems

2000 MWe

ENEL Experience, ItalyENEL Experience, Italy

Reflection SeismicsReflection Seismics

Major fault zones

~ 4 km depth

700 MWe

MT, 3-D InversionMT, 3-D Inversion

Excellent imaging down to 2-3 kmExcellent imaging down to 2-3 km Need for noise filtering at low frequencies

Sophisticated algorithmsSophisticated algorithms Demanding computing equipment

Interpretation:Interpretation: Better starting point for the Earth Scientist

Correlation with drilling & other data