Hydrothermal circulation

Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, water,^[1] and θέρμη, heat ^[1]). Hydrothermal circulation occurs most often in the vicinity of sources of heat within the Earth's crust. In general, this occurs near volcanic activity,^[2] but can occur in the shallow to mid crust along deeply penetrating fault irregularities or in the deep crust related to the intrusion of granite, or as the result of orogeny or metamorphism. Hydrothermal circulation often results in hydrothermal mineral deposits.