Photo by Jennifer Boyer: Geothermal Greenhouses in Hveragerði, Iceland. Geothermal Greenhouses: A...

Small chips of rocks (e.g., <1/8 inch or <3 mm) obtained during drilling with a rotary bit that are continuously returned to the surface by the circulation of mud. Drill cuttings are the main source of geological and stratigraphic interpretation in the drilling of geothermal and oil-gas wells.
Felsic A geological term referring to igneous rocks that are equivalent to rhyolite and granite in composition.
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...
Fumarole A steam vent and surface thermal feature that is commonly associated with steaming ground and mud pots in hydrothermally and volcanically active areas.