More than 19,000 seamounts, or underwater mountains, have been uncovered by a team of scientists. The discovery was made using satellite data by the researchers. The team that found the seamounts was led by data analyst Julie Gevorgian of the Scripps Institute of Oceanography in California.
Only 20% of the ocean floor has been mapped by ships, according to a recent publication by Gevorgian’s team. They also claimed that thousands of additional seamounts may still be undiscovered.
The seamounts are formed by volcanic activity on the ocean floor and can reach heights of 3 to 10 kilometers (about 2 to 6 miles). Claire Watson, the author of an earlier report on the discovery, claims that smaller seamounts (less than 2 km) are more difficult to find as they “… tend to form near mid-ocean ridges where magma pushes through Earth’s thin and fractured crust.”
She also said the seamounts can “rise thousands of meters in the darkness [of the deep sea], putting unsuspecting submarines at risk.”
Three-quarters of Earth’s volcanic activity, according to the National Oceanic and Atmospheric Administration, occurs underwater. Yet, not all of the undersea volcanoes are active.
How then do we locate the seamounts? Sonar, a method that uses sound waves to bounce off the ocean floor, can be used by ships to find them. But only when the ships happen to travel over the seamounts can that occur.
A new method, known as satellite altimetry, was employed by Gevorgian’s team to monitor changes in sea surface height rather than the actual sea floor. The presence of seamounts (the volcanoes) on the ocean floor can enhance the gravitational force, which can be seen as a shift in the height of the sea surface.
“Using this method, Gevorgian and colleagues identified 19,325 new undersea volcanoes, adding to the 24,643 mapped seamounts that two members of the team had previously cataloged back in 2011 and ironing out some mistakes in the process.
In fact, that brings the total to 43,454 undersea mountains, almost doubling the number we knew about,” wrote Watson.
