Australia has selected Dutch firm Fugro Survey Pte Ltd to be the prime contractor in managing the deep-water search in the southern Indian Ocean for Malaysia Airlines Flight MH370 missing since March
8.

Australian Deputy Prime Minister Warren Truss said Fugro would use two vessels equipped with towed deep-water vehicles and carrying expert personnel to undertake the search operations.

"The vessels will search the sea floor using side scan sonars, multibeam echo sounders and video cameras to locate and identify the debris.

"I remain cautiously optimistic that we'll locate the missing aircraft within the priority search area," he told a press conference in Canberra which was also streamed online today.

Truss said the Perth-based firm was familiar with the Australian operation in the search for MH370, offering "the best value-for-money technical solution" for the undersea search.

Currently, the firm's vessel, Fugro Equator, is undertaking a bathymetric survey in the new search area, together with the Chinese navy's Zhu Kezhen.

Truss said the survey had covered 60 per cent of the area, or around 32,000-sq km, since it started in April.

The Beijing-bound Malaysian plane with 239 people aboard went missing in the early hours of March 8 shortly after departing from the KL International Airport.

It was to have arrived in Beijing at 6.30 am on the same day.

An analysis of satellite data indicated that the plane's last position was in the southern Indian Ocean, west of Perth, Australia.

On May 29, the Joint Agency Coordination Centre set up by Australia discounted the vicinity of several acoustic signals detected in the southern Indian Ocean in early April as the final resting place of MH370.

Following the event, Australia announced on June 26 that the search area for MH370 would be shifted further south to an area of about 60,000 sq km along what is known as the 'seventh arc' in the Indian Ocean.

Meanwhile, Australian Transport Safety Bureau (ATSB) chief commissioner Martin Dolan said the bathymetric or mapping of the sea floor survey so far had discovered some anomaly related to the geology of the ocean floor.

"The north area is comparatively flat and deep, and it rises towards the south and the terrain becomes more difficult.

"We haven't completed the mapping ... (and) still discovering details, features that we had no knowledge of (previously) - underwater volcanoes and various other things. So, we're finding some surprises as we go through," he said.

Dolan did not rule out the possibility of underwater canyons "hiding" the aircraft.

Malaysia Airlines was hit by another tragedy when Flight MH17 en route from Amsterdam to Kuala Lumpur with 298 people aboard, including 43 Malaysians, went down over eastern Ukraine on July 17.

International investigators are trying to piece together what really happened to the Boeing 777 plane, the challenging task compounded by the fact that it crashed in a troubled region between Ukraine and Russia.