Oceanographers Team Discover Over 19,000 of Underwater Volcanoes
- NOAA
So, scietists set out to explore and map as many seamounts as possible, in order to understand what lies on the ocean floor a little better.
The 19,325 seamounts discovered were previously unknown to science. The satellites used to discover them could not take pictures of the seamounts, but they were able to discern differences in the altitudes and gravitational pull.
"There can definetly be many more small seamounts globally. Our current altimetry data has a resolution of about 6 km, which means seamounts with a diameter smaller than 6 km will not be located," Gevorgian explained.
"These small seamounts have smaller mass and produce smaller gravity signatures which are difficult to identify in the altimetry data. For example, this might be the case near fast spreading ridges which can have many small volcanoes," he added.
Foto satelit erupsi gunung berapi bawah laut di Tonga yang memicu tsunami.
- NOOA-BBC
Previous studies such as Kim & Wessel, 2011 have mentioned that there could be 50,000 globally and the amount of them increases with a decrease in size.
Our study, Gevorgian said, definitely helped make progress in the global seamount catalog, but improvements in the data resolution can help us find more.
The new seamounts discovered in this study will be added to the 2011 Kim–Wessel catalog, also known as the Global Seamount Database which, before this research, mapped 24,643 seamounts. There are now a total of 43,454 seamounts mapped.
According to the National Oceanic and Atmospheric Administration, three-quarters of all of Earth's volcanic activity happens in deep water. Sometimes, but very rarely, eruptions can be dangerous. Underwater volcanoes can trigger tsunamis, however, to do so, they have to not be too far below the sea surface.
It is usually uncommon for seamounts to have explosive eruptions like some we see on land volcanoes.
This is because, at these depths, the water pressure creates an immense weight. So when an underwater volcano erupts, it will create a passive lava flow along the seafloor. These eruptions usually cannot be seen at the surface of the ocean.
