Cold seep
A cold seep (sometimes called a cold vent) is an area of the ocean floor where hydrogen sulfide, methane and other hydrocarbon-rich liquids leak out of the Earth's crust, often in the form of a brine pool. Cold seeps form a biome supporting several native species.
Cold seeps change the shape of the ocean floor over time, where reactions between methane and seawater create carbonate rock formations and reefs. These reactions may change when bacteria are present.
Types
Cold seeps at different depths have different names. Other kinds of cold seeps are:
- oil/gas seeps
- gas seeps: methane seeps
- gas hydrate seeps
- brine seeps are forming brine pools
- pockmarks
- mud volcanos
Formation and ecological succession
Cold seeps occur over cracks in the seafloor caused by the movement of the Earth's crust. Oil and methane "seep" out of those cracks, get dissolved by tiny bits of rock, and emerge over an area several hundred meters wide.
Methane (
Cold Seep Media
Close-up photograph of the symbiotic vestimentiferan tubeworm Lamellibrachia luymesi from a cold seep at 550 m depth in the Gulf of Mexico. The tubes of the worms are stained with a blue chitin stain to determine their growth rates. Approximately 14 mo of growth is shown by the staining here.
Bacterial mat consisting of sulfide-oxidizing bacteria Beggiatoa spp. at a seep on Blake Ridge, off South Carolina. The red dots are range-finding laser beams.
A mussel bed at the edge of the brine pool
"Roots" of tubeworms also provide a supply of hydrogen sulfide from the sediment to the bacteria inside these tubeworms.
Symbiotic vestimentiferan tubeworm Lamellibrachia luymesi from a cold seep at 550 m depth in the Gulf of Mexico. In the sediments around the base are orange bacterial mats of the sulfide-oxidizing bacteria Beggiatoa spp. and empty shells of various clams and snails, which are also common inhabitants of the seeps.
Tubeworms, soft corals, and chemosynthetic mussels at a seep located 3,000 m (9,800 ft) down on the Florida Escarpment. Eelpouts, a Galatheid crab, and an alvinocarid shrimp feed on mussels damaged during a sampling exercise.
Lamellibrachia tube worms and mussel at a cold seep 
The crewed submersible DSV Alvin, which made possible the discovery of chemosynthetic communities in the Gulf of Mexico in 1983.
Chemosynthetic communities in the northern part of Gulf of Mexico around cold seeps known in 2000
CH4) is the main part of what we commonly refer to as natural gas. But in addition to being an important energy source for humans, methane also forms the basis of a cold seep ecosystem.