Geothermal Geophysics Pre Mid

A geothermal system that indicates a high production rate are as following, except:

• Potent heat source

• Benign fluid

• Average heat gradient

• Good permeability

Geological conditions that increases permeability are as following, except:

• Blockage by mineral deposition

• Fracturing, faulting

• Rejuvenation of geologic structures

• Hydrothermal leaching

These are following parameters affecting alteration:

• temperature

• type of origin rock

• type of reservoir

• fluid composition

Classification origin of geothermal fluid are as following

• Magnesium

• Chloride

• Sulfate

• Bicarbonate

Which geological aspect is a good indicator of high geothermal prospect?

• age volcanism quaternary ; rock alteration active

• age volcanism recent ; rock alteration active

• age volcanism tertiary ; rock alteration active

• age volcanism quaternary ; rock alteration relic

Which geothermal fluid can be used for geothermometer?

• magnesium

• sulfate

• bicarbonate

• chloride

Good quality of geophysical aspect for scoring are as following:

• 25% data good/excellent quality; full tensor and tipper

• 75% data good/excellent quality; full tensor and tipper

• 75% data good/excellent quality; Zxy and Zyx

• 75% data good/excellent quality; full tensor

Why does distance to coastal line needs to be considered in acquisition?

• sea water intrusion can effect gravity result

• sea water intrusion can give misleading result in resistivity

• sea water intrusion can effect MT result

• sea water intrusion can effect magnetic result

Magnetotelluric is very useful in exploring conventional geothermal system for:

• identifying clay cap and reservoir dimension

• possible heat source of geothermal system

• fracture prediction of reservoir

• fluid circulation in geothermal system

Clay cap is identified by different aspect as following

• conductive layer (< 10 ohm.m)

• smectite illite minerals

• propylitic minerals

• slightly resistive layer (tens of ohm.m)