hydrothermal

Hydrothermal denotes processes, environments, or systems involving hot water, typically at elevated temperature and pressure. It describes the interaction of hot aqueous fluids with rocks, which can transport dissolved minerals, drive geological alteration, and influence biological communities in certain habitats. In laboratory settings, hydrothermal conditions are used to synthesize materials and study mineralization.

Natural hydrothermal systems occur where groundwater is heated by magma or geothermally heated rocks, circulating through crustal rocks. Seafloor hydrothermal vents emit mineral-rich fluids that exceed ambient sea temperature and support ecosystems based on chemosynthesis. Since their discovery in 1977 at mid-ocean ridges, vents have revealed diverse vent fields, with black smokers and white smokers representing different mineralogy and chemistry.

Hydrothermal processes contribute to ore formation, including porphyry copper deposits, epithermal veins, and other hydrothermal ore bodies formed when hot fluids deposit metals as they ascend and cool.

In energy and technology, hydrothermal refers to systems where hot water or steam is used for geothermal power, direct heating, or industrial processes. In chemistry, hydrothermal synthesis uses aqueous solutions at elevated temperature and pressure in sealed vessels to crystallize materials such as zeolites and metal oxides.

The concept encompasses both natural phenomena and engineered systems, highlighting the role of heated water in transport, mineralization, energy production, and materials science.