Photo by Jennifer Boyer: Geothermal Greenhouses in Hveragerði, Iceland. Geothermal Greenhouses: A...
Illite
A potassium-bearing mica-like clay mineral that is a product of hydrothermal alteration. It commonly replaces feldspars and other alumino-silicate minerals and it forms above ~220°C. It also reflects a weakly acidic pH condition in hydrothermal fluids.
Geothermal Glossary
Word of the Week – Epidote
Epidote Alumino-silicate hydrothermal mineral having a distinctive yellow-green color that is used a mineral geothermometer, forming at temperatures above ~230°C. The first down hole occurrence of epidote commonly coincides with the top of a high-temperature...
Word of the Week – Felsic
Felsic A geological term referring to igneous rocks that are equivalent to rhyolite and granite in composition.
Word of the Week – Flowback
Flowback Return flow of slickwater that was injected during a stimulation. This is a highly controlled process in which well head pressure is reduced to allow managed fluid recovery. Fluids are commonly sampled and chemically analyzed to determine the effects of...