NOAA rendering of a brine pool in the Gulf of Mexico.

Brine pools are large areas of brine on the ocean basin. These pools are concentrations of water having an extremely high salinity as compared to the surrounding ocean, caused by the motion of large salt deposits through salt tectonics. Methane is also in high concentration in these areas, providing energy by the process of chemosynthesis to creatures which live in the pool's vicinity. These creatures are often extremophiles.^[1]

Characteristics

Brine pools are considered "lakes" within the ocean by many oceanographers. This is due to the high salinity of the water in the pool, which prevents water of lower salinity from entering and creates a distinct surface and shoreline for the pool.^[2]

Support of life

Cold seep activity often coincides with the location of a brine pool. Methane released by the seep is processed by bacteria, which have a symbiotic relationship with mussels and other lifeforms at the edge of the pool. This ecosystem is entirely dependent on chemical energy, and unlike almost all other life on Earth, has no reliance on energy from the sun. ^[3]

Effect on submarines

Submarines which come across brine pools float on top due to the high salt concentrations, creating ripples that cause the surrounding habitat, the "shore", to bob up and down. ^[4]

References