The Utah FORGE Geothermal Song Parody Contest — Engaging Students Through Song By Sarah Buening...

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), epidote, calcite and pyrite, imparting a dark green tint to the appearance of altered rocks. It is commonly developed in volcanic-plutonic sequences that host high-temperature geothermal reservoirs.
Fumarole A steam vent and surface thermal feature that is commonly associated with steaming ground and mud pots in hydrothermally and volcanically active areas.
Geochemical Tracer An environmentally benign chemical that is injected to trace fluid movement through the geothermal reservoir and that can be easily detected in produced hot fluid.
Geothermal Gradient The increase in temperature with depth below the surface, usually reported in units of °C/km.