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...

Fumarole A steam vent and surface thermal feature that is commonly associated with steaming ground and mud pots in hydrothermally and volcanically active areas.