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Introduction

Hydrothermal Vent, spring of hot water on the deep ocean floor. The water is heated in Earth’s crust by volcanic magma or in the mantle by a process called serpentinization (a chemical reaction between water and certain minerals). Heated water circulating up through the crust becomes enriched with minerals and chemicals. The minerals precipitate out when the hot water meets the cold water and intense pressure on the ocean floor, forming chimneylike and towerlike structures. The enriched hot water also provides food and energy for extremophile microorganisms that use chemical processes (chemosynthesis) instead of sunlight (photosynthesis) to produce food. Other life forms in turn use the microorganisms and their byproducts as food, forming unusual ecosystems known as hydrothermal vent communities.