Scientists from the University of New Hampshire recently discovered a seamount that could be the remains of an ancient extinct underwater volcano.
The scientists stumbled upon the seamount while taking part in a seafloor mapping mission on-board the R/V Kilo Moana, a U.S. Navy oceanographic research ship operated by the University of Hawaii. The mission's goal was to map the borders of the U.S. Continental shelf in the Pacific Ocean.
The mapping mission uses multibeam echosounders, a sonar technology that maps out and delineates the contours on the surface of the ocean's floor. The seamount appeared on the mission's images "out of the blue."
Researchers found the seamount about 186 miles from an uninhabited island called Jarvis Island and exists in a part of the ocean that is not often explored. Therefore, scientists weren't too surprised by its appearance.
"These seamounts are very common, but we don't know about them because most of the places that we go out and map have never been mapped before," says James Gardner, research professor in the UNH-NOAA Center for Coastal and Ocean Mapping/Joint Hydrographic Center.
Although satellites can map out the Earth's seafloor, they do so at a low resolution. This means that satellites don't see as many features of the ocean's floor, such as these seamounts. However, sonar technology like the multibeam echosounders, give a much more detailed picture.
A seamount is a mountain that rises from the ocean's floor, but does not reach the water's surface. These are usually extinct volcanoes that rise at least 3,000 feet above the seafloor.
These ancient underwater volcanoes are fascinating. Many of these structures host a variety of marine life and host their own ecosystems with fish, plankton, corals and marine mammals. Some host huge fisheries. However, none of the known seamounts have been thoroughly studied by scientists.
This newly discovered seamount, though, is so far underwater that it could be vastly different and not host any marine life. In fact, it is so far underwater that it isn't even considered a navigational hazard for boats.
"It's probably 100 million years old," says Gardner, "and it might have something in it we may be interested in 100 years from now."
The seamount's location is within the borders of the U.S. economic zone. This means that the U.S. owns jurisdiction of the seamount, along with its rocks and sediments.