Final answer:
The geotherm is the rate of change of temperature with increasing depth in the Earth's crust.
Step-by-step explanation:
The geotherm is the rate of change of temperature with increasing depth in the Earth's crust. It is a measure of how the temperature changes as you go deeper into the Earth. The geotherm is typically expressed in degrees Celsius per kilometer (°C/km). For example, if the geotherm is 30°C/km, it means that the temperature increases by 30 degrees Celsius for every kilometer you go deeper into the Earth.