Deep-sea hot springs

Part of Hall of Planet Earth.

Deep Sea Hot Springs AMNH/R.Mickens

Driven by heat from molten rock, the entire ocean circulates every one to ten million years through the crust along the mid-ocean ridges. About 80 percent of the Earth’s internal heat escapes in this way. This vast circulation — the underwater hydrothermal system — influences the composition of the ocean. The circulating hot seawater deposits some elements, such as magnesium, in the crust, and dissolves other elements, particularly metals, adding them to the ocean.

In This Section

Exhibit How hydrothermal systems work At mid-ocean ridges, cold seawater is forced to circulate through an extensive system of cracks above bodies of molten rock. Exhibit How sulfide chimneys form Tiny particles of metal sulfide and oxide minerals, resembling black “smoke,” billow from the hot-water vents.