Undersea mountain ranges are a huge interconnected mountain system that extends more than 40,000 miles through the Atlantic, Pacific and Indian oceans. The best known among them is the Mid-Atlantic ridge. Many of the mountains formed at the mid-ocean ridges have been carried away from the ridge as new ocean crust forms and sea floor spreads apart.
Volcanoes not only erupt from the land but can also erupt from under the sea. Such volcanoes are called submarine volcanoes or seamounts. A seamount is a mountain rising from the ocean seafloor that does not reach water level. The undersea volcanic eruptions are a constant process that shapes the features of the ocean. Seamounts are volcanoes scattered across the Pacific Ocean floor. These are thousands of feet high. The eruptions cools down quickly compared to volcanic eruptions on land.
It has been found that there are about 30,000 seamounts across the globe. Many present day islands were actually formed by submarine volcanic eruptions. The mid ocean ridges are volcanic mountain ridges formed where new material is formed on the seafloors along the crustal plates.
Seamounts are not just mysterious spots but are of great biological significance. They provide food and support to various marine life forms. Ridges and seamounts are powerful enough to exert a gravitational pull that makes sea levels drop by as much as 10cms. They grow up through the ocean and have steep slopes. Water current hits these slopes stirring up the nutrients for the flourishing life forms near them.
There is another kind of undersea mountains called guyots. These mountains have flat, table like tops which may be due to the constant shearing off by the waves at a time when the mountaintops were near the surface of the sea. The sagging of the ocean floor might cause them to lower far below the surface level.
The satellites are the best tool to map these mountains on the seafloor. With the rise in the release of carbon dioxide into the atmosphere, the marine life forms on the sea floor are facing threat. It is predicted that rise of carbon dioxide could result in the acidification of ocean water which may dissolve the skeletons of life forms like corals. This kind of marine ecosystem found deep inside the ocean are also helpful in research into treatments for diseases like cancer and malaria.