Definitions for "Geothermal Gradient"
Keywords:  gradient, depth, deeper, thermal, crust
The progressive increase of temperature with depth into the Earth.
The rate at which temperature increases with increasing depth below the Earth's surface; a general average is around 30ºC increase per additional km of depth.
The rate of increase of temperature in the Earth with depth. The gradient near the surface of the Earth varies from place to place, depending on the heat flow in the region and on the thermal conductivity of the rock. Approximate average geothermal gradient in the Earth's crust is about 25ºC/km.