Robot sub to seek clue on P&W Terraces

Image via Wikipedia
Robot sub to seek clues on P&W Terraces...


ROBOT RESEARCH: A Remus submarine, image, will search for the Pink and White Terraces, bottom.
A yellow submarine used by the US Navy to help clear mines off Iraq will dive in Lake Rotomahana this month to find out what happened to the Pink and White Terraces.

Shaped liked a 2m torpedo, the Remus 100 - an autonomous underwater vehicle packed with instruments so it can take precise measurements - is being brought to New Zealand to help scientists looking for signs of geothermal activity at the bottom of the lake.

They hope it will enable them to map the lakebed and discover what happened to the Pink and White Terraces hydrothermal system after the 1886 Tarawera eruption.

The battery-powered device will travel along programmed co- ordinates at walking pace, following the shape of the lake floor, while taking measurements of the temperature, acidity, water clarity, magnetism, and the electrical potential and conductivity of the water.

The data will be compiled into a three-dimensional map that will show features as small as a metre across.

It is expected to take two of the machines a fortnight to map the lake, which is 3km by 6km and 115m deep.

If the mapping is successful, scientists plan to return to do a seismic survey over areas of the lake with the most active hydrothermal vents.

That will show the general architecture of the geothermal system beneath the lake floor, which will be the best opportunity to reveal any remnants of the famous terraces.

Project leader Cornel de Ronde said the aim was to discover what happened to the terraces after the Tarawera eruption. Before the eruption the terraces were considered the eighth natural wonder of the world.

The largest silica terraces in the world, they represented an enormous outflow of geothermal fluid.

"Most of us believe their demise came from the eruption and there is a lot of evidence to show that there is probably a very big crater down there . . . but nobody has seen this landscape for 150 years," de Ronde said.

"What these instruments can do is hug the lake floor and map it, so we can render a high resolution image . . . as if you were standing on the edge of the lake looking in at what has happened."

Acknowledgements:- Sunday Star Times

Related articles

• Underwater explorers seek lost New Zealand wonders (gadling.com)
• Geothermal answer: Can geothermal energy be renewed (wiki.answers.com)