You searched for: “geothermometry
1. The direct or indirect measurement or approximation of the temperatures at which geologic processes take place or have taken place.
2. The study of the earth's heat and temperatures, and their effects on geologic processes.
3. The study of the earth's heat and subsurface temperatures.
4. In geology, a mineral or aggregate of minerals whose presence defines the temperature range of limits within which the minerals were formed; also known as a geologic thermometer.