A 9-hour circulation test that followed stimulation proved fluid flow and energy transfer from an EGS reservoir in hot dry granite …
Gneiss
Metamorphic rock that forms under intense pressure and high temperature and that is made of quartz, feldspar, amphibole and mica. Gneiss represents the highest grade of metamorphic rock, which is characterized by alternating bands of dark and light-colored minerals, foliation (i.e., parallel alignment of planar minerals) and tight folding. This rock type is common at mid to deep levels of continental crust.
Geothermal Glossary
Word of the Week – District Heating
District heating A scheme for distributing centrally produced thermal energy via a network of pipes to heat residential and commercial buildings. Such schemes are energy efficient and ideally suited for utilizing geothermal resources.
Word of the Week – Dolomite
Dolomite A carbonate mineral similar to calcite in which magnesium partially substitutes for calcium.
Word of the Week – Drill Bit
Drill Bit A tool that is placed on the end of a string of pipe to drill a well. Rotary drill bits are commonly used in oil and gas and geothermal drilling. Coring bits are used to obtain cylindrical core samples of rock that preserve mineralogical and textural...