UK scientists have released images of the ocean floor near the epicentre of December's giant Asian earthquake.

They were obtained by the Royal Navy's hydrographic survey ship HMS Scott.

The three-dimensional pictures detail the deformed seabed 150km (94 miles) off the Sumatran coast, and reveal huge underwater landslides.

Researchers involved in the project believe the images may help in the design of the tsunami early warning system to be built in the region.

"There are features which we would think are something like the Grand Canyon would look," Tim Henstock, one of the scientists on board HMS Scott, told BBC News.

"You can see huge piles of mud maybe a few hundred metres thick; there's lots of evidence of activity at the subduction zone."

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"The big question at the moment is why the earthquake occurred where it did, and all the aftershocks were then further to the north," Russell Wynn told the BBC News website.

A marine geologist at Southampton Oceanographic Centre, Dr Wynn is processing data sent back to the UK from HMS Scott by scientists on board, such as his Southampton colleague Tim Henstock.

"The area to the south of the earthquake epicentre seems to be relatively unaffected," he said. "So one of the things this survey will try to understand is why that area was not affected, and is that an area where some time in the future there may be an earthquake?"

This information may prove vital in setting up an early-warning system.

There have recently been disputes between some of the governments involved, principally over where to site the system's co-ordinating centre; but from a scientific perspective, it is much more important to find the right sites for the sensors which will feed information to that centre.

"This really was a grey area of seabed; we didn't have any information at all of any quality," said Dr Wynn.

"So by doing this detailed map we will get an idea of where to site monitoring equipment on the seabed, and that monitoring equipment will then feed into early warning systems that hopefully some time in the future will contribute to saving lives."...