Geothermal energy is the Earth’s internal heat and also the use of that heat as an energy source.
The word comes from:
The Earth’s internal heat is generated primarily by the radioactive decay of elements such as uranium, thorium, and potassium; residual heat from the planet’s formation; and processes within the Earth’s core and mantle. This heat is transmitted to the surface.
Geothermics helps us understand the Earth’s heat flow; the thermal evolution of basins; the cooling of rocks; volcanic activity; fluid circulation; and tectonics and the formation of mountain ranges
It is also closely related to thermochronology; tectonics; volcanism; and geodynamics
Geothermal science is key because thermochronological methods record how rock temperatures change during burial; tectonic uplift; erosion; and cooling