British Sign Language Glossaries of Curriculum Terms

BSL Environmental Science Glossary - Hydrothermal deposition definition

Definition: Hydrothermal deposition occurs when a mineral is deposited from a mineral-rich solution. Igneous rocks are formed from magma that cools and solidifies within the Earth's crust. The intrusions produce pressurised superheated water at high temperatures dissolving many minerals from the surrounding rocks. These mineral-rich solutions travel along the fissures away from the magma, cooling as they do. As they cool, the dissolved minerals crystallise and come out of solution. Metal ores that are deposited by hydrothermal processes include tin, copper, lead, silver, gold and arsenic.