|Live Science | Oct 2, 2014|
Scientists have created some of the most vivid maps yet of the deepest and most mysterious spots beneath the ocean. Their effort, detailed in the Oct. 3, 2014, issue of the journal Science, has uncovered thousands of undersea mountains called seamounts that rise up from the seafloor. To create the seafloor map, which covers the world's oceans, the scientists relied on measurements taken from high-resolution altimeters onboard the European Space Agency's (ESA) CryoSat-2 satellite and NASA's Jason-1 satellite, along with information resulting from new data-processing methods. The results also shed light on seafloor tectonics, or the movements of massive oceanic plates that can shape the rifts, ridges and trenches decorating the ocean bottom. Here's a look at what the researchers uncovered.
The satellite altimeters worked by bouncing a radar signal or laser off the surface of the ocean being targeted and measuring how long it took the signal to return. That time can reveal the dips and peaks, or topography, of the ocean surface to within centimeters, scientists say. The sea-surface topography roughly mirrors changes in Earth's gravity. For instance, if an underwater volcano or mountain were hidden along the seafloor, the structure would push up against the sea surface and cause it to bulge. A trench, on the other hand, would cause the surface to sag.