Did you know… Alaska uses geothermal energy to produce electricity? It might seem highly unlikely...

Porous and permeable rock unit or unconsolidated layer in the subsurface in which all the pores and voids are filled with water. Water supply for wells comes from aquifers.
Proppant Sand-sized solid grains that are injected in a fluid suspension and used to hold open stimulated fractures in a geothermal reservoir.
Propylitic Alteration A term borrowed from studies of hydrothermal ore deposits that refers to an assemblage of secondary hydrothermal minerals which forms in igneous rocks. This assemblage is made up of chlorite, illite, feldspar (both Na and K-rich varieties),...
Rhyolite Light colored fined grained volcanic rock composed of glass, quartz, K-feldspar and plagioclase, with relatively high silica (69-77 wt %). The composition reflects partial melting of continental crust. Rhyolitic volcanism is a feature of both Yellowstone...