Claire Duffin, The Telegraph | September 29, 2014 | Last Updated: Sep 29 2:23 PM ET
A Fugro autonomous underwater vehicle (AUV) that is part of a new high-resolution search for missing
Malaysia Airlines flight MH370 that is set to begin in early October, after the mapping of some
110,000 square kilometres of the remote area's vast sea floor. FUGRO/AFP/Getty Images
Until now, scientists had better maps of the surface of Mars than of this ocean floor.
These images show for the first time a dramatic underwater landscape with mountains higher than Mont Blanc and ridges deeper than the Grand Canyon – all 4.5 kilometres below the surface of the Southern Indian Ocean.
The discoveries were made as part of the hunt for the missing Malaysian airliner, flight MH370, which disappeared six months ago.
Experts used pulses of sound, which are bounced off the sea bed, to uncover this previously uncharted world.
GEOSCIENCE AUSTRALIA/AFP/Getty ImagesThis image shows the MH370 search area encompassing the seabed on and around Broken Ridge, an extensive linear, mountainous sea floor structure that once formed the margin between two geological plates. Remnants of volancoes, 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.
The resulting 3D maps reveal mountain ranges, with some peaks more than a mile high, trenches 1.4 km deep and what is believed to be a submarine volcano, bigger than Mount St. Helens.
The maps cover an area either side of a range known as Broken Ridge, around 1,770 km off the west coast of the Australian city of Perth.
It once formed the margin between two geological plates that separated between 20 and 100 million years ago.
“The terrain of the area around Broken Ridge makes the European Alps look like foothills,” said Dr. Simon Boxall, a lecturer in ocean and earth science at the University of Southampton.
“If you stood in the valley you would have, towering above you, mountains that were about 3 kmhigh – just coming straight up in front of you.”
The maps were produced by the Australian Transport Safety Bureau (ATSB), which is leading the search for the missing passenger plane.
FUGRO/AFP/Getty ImagesThe Australian-contracted survey ship M/V Fugro Equator, which, along with the Chinese survey ship Zhu Kezhen, has mapped some 110,000 square kilometres of the remote area's vast sea floor in preparation for the start of the high-resolution search for missing Malaysia Airlines flight MH370 in early October.
The aircraft vanished without trace on March 8 this year with 239 people on board. It was en route to Beijing from Kuala Lumpur when it disappeared, having taken an inexplicable about-turn and headed almost due south.
Despite a massive search operation, involving 26 countries and stretching from the Gulf of Thailand to the Bay of Bengal and, finally, the Indian Ocean, no trace of the plane, or even its black box, has been found.
The search was narrowed in April after “pings” from the plane’s satellite communication system placed it somewhere along a 2,485-mile curve in the Southern Indian Ocean known as the “seventh arc.”
Experts believe this area, which is around 60,000 square kilometres – roughly the size of Croatia – is where the aircraft’s fuel ran out. An international fleet of ships and aircraft searched the area for six weeks, between March 18 and April 28, but found no debris on the surface.
GEOSCIENCE AUSTRALIA/AFP/Getty ImagesThis image shows the MH370 search area encompassing the seabed on and around Broken Ridge, an extensive linear, mountainous sea floor structure that once formed the margin between two geological plates.
The next stage of the search involves going underwater. But before this could begin, the ATSB has had to produce these maps.
It is working with Geoscience Australia on the bathymetric survey, which involves obtaining measurements of the depth of the ocean and is equivalent to mapping topography on land. So far, 41,300 sq kilometres of the search area have been analyzed and mapped, revealing contours, depths and hardness of the ocean floor.
The work is expected to take 12 months to complete.
What you are doing is flying a piece of equipment very close to the sea floor and if you don’t know what is there in the first place, you end up driving into a mountain
While the maps are too coarse to find any actual wreckage from the plane, they do provide the first detailed look at this part of the ocean floor.
They are also vital for the next stage of the search – when two or three deep-sea search vehicles examine the seabed for debris. The equipment is pulled along just above the sea floor by a six-mile long armoured cable and scientists need to know if they are likely to encounter mountains and valleys.
AP Photo/Rob GriffithAn observer on a Japan Coast Guard Gulfstream aircraft takes photos out of a window while searching for the missing Malaysia Airlines Flight MH370 in the Southern Indian Ocean. on April 1, 2014.
“Before you can do the next level of detailed search, you need to know what is there,” Boxall said.
“What you are doing is flying a piece of equipment very close to the sea floor and if you don’t know what is there in the first place, you end up driving into a mountain. Not only does this mean you end up writing off a million pounds worth of equipment, you also put the people on the ship in great risk because someone driving several tons worth of kit into the sea floor causes huge strain on the cable.
“It means they now have enough information to search safely.”
The images are coloured to show depth, which ranges from 2.5 km m to 5.3 km.
Boxall said it was this depth, and the difficulties of using equipment at these depths, which meant that much of the world’s oceans were still unknown. Almost 72% of the planet is covered in water yet the majority of it has never been mapped.
FUGRO/AFP/Getty ImagesThe Australian-contracted survey ship M/V Fugro Discovery.
“We can’t use the normal techniques, like Google Earth, radar and satellites to build up terrain maps like we can on land. None of that works under water.
“You can’t penetrate seawater with radar or light. They all only look at the surface. So you have to use sound and it is a very slow process. It’s a vast area and it is deep – the depth here is three to four kilometres so it is very inaccessible, that is the problem.”
The dramatic undulations shown in the new maps are believed to be the result of volcanic eruptions.
Those things that look like little humps – each one is about the size of Ben Nevis. They are about 1.5 km high
“When you look at it, it looks absolutely stunning but it also gives you an idea of the enormity of this area,” Boxall said.
“Those things that look like little humps – each one is about the size of Ben Nevis. They are about 1.5 km high, they are about 5 km across – so they are quite dramatic. If you saw those sitting on land you would think ‘wow.’
“As you go further, towards that broken ridge area, that is a bit bigger than the Alps. So if you put the French Alps and the Grand Canyon together, they would sit quite neatly in that little area – it is hard to imagine how big it is.”
GEOSCIENCE AUSTRALIA/AFP/Getty ImagesA three-dimensional model of the seafloor terrain based on sparse pre-existing data, some of which has been derived from satellite gravity measurements and some from ocean passage soundings. Remnants of volancoes, towering ridges and deep trenches have now been discovered on the seabed of the southern Indian Ocean by experts mapping the underwater terrain.
The underwater search for the plane is expected to start next month.
The vehicles will use sonar to scan the ocean floor for anything that might resemble MH370. They can also detect the presence of aviation fuel.
While the families of the passengers on board MH370 hope the searches will provide answers, Boxall said he believed the chances of finding MH370 were still “very slim,” despite the improved mapping.
“Sadly, they will have to decide where to draw the line,” he said. “It will be a question of tripping over it luckily. They could still go over it and miss it, it could have sunk deep into the sediment.
“The ocean is so vast, it is almost an impossible task.”
Source: http://news.nationalpost.com/
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