Malaysian MH370

Flight MH370's grave may be deep in southern Indian Ocean's trenches


Deep underwater volcanoes and towering ridges discovered on sea floor by Australian authorities searching for missing flight

More than 106,000 sq km of the search area in the southern Indian Ocean have been surveyed. Photograph: Australian Transport Safety Bureau

Remnants of volcanoes, towering ridges and deep trenches have been discovered on the seabed of the southern Indian Ocean by experts mapping the underwater terrain as part of the search for missing Malaysian Airlines flight MH370.

Australian authorities have released the three-dimensional images, revealing for the first time details about the sea floor where efforts are being concentrated to find the jet, which is presumed to have crashed into the sea on 8 March.

The area in which the plane is thought to have gone down is remote and largely unexplored, and officials are conducting an intensive survey of the seabed before the underwater probe for the plane can begin.

"The recently acquired high-resolution bathymetry [underwater survey] data has revealed many of these seabed features for the first time," the Australian Transport Safety Bureau, the agency leading the search, said in a statement.

"It is also revealing finer-scale seabed features that were not visible in the previous low-resolution, satellite-derived bathymetry data."

The MH370 search area off Western Australia includes the seabed on and around an extensive, mountainous ridge that once formed the margin between two geological plates.

The expanse has many of the features typically found in such areas, with tectonic movements having created now-extinct volcanoes, rugged ridges up to 300m high and trenches 1,400m deep compared with the surrounding sea floor, the bureau said.

The bureau said identifying these features would help navigation during the underwater search phase - due to begin in October - for the Boeing 777.