[meteorite-list] Possible Ancient Impact Crater Australia

From: Darren Garrison <cynapse_at_meteoritecentral.com>
Date: Mon, 17 Mar 2008 19:43:59 -0500
Message-ID: <gu3ut3liq53lmbjtv8nh1srecpae9mq7jc_at_4ax.com>

http://www.sciencealert.com.au/news/20081803-17058-2.html

 Satellite image reveals new crater
Tuesday, 18 March 2008
ScienceNetwork WA By Michelle Ridley

The Hickman Crater as seen on Google Earth

Next time you?re virtually roaming Google Earth, make sure you take a close look
at any unusual landforms.

Geologist Arthur Hickman did just that, and is now the proud parent of the
Hickman Crater, a meteorite crater in the Hamersley Ranges.

Dr Hickman, from the Geological Survey of Western Australia, was using Google
Earth to look for iron ore when he noticed an unusually circular structure.

He sent a Google Earth picture of the structure to his colleague Dr Andrew
Glickson at the Australian National University, who later visited the area and
confirmed that Dr Hickman had found a particularly well preserved meteorite
crater.

?Our best estimate at the moment is that the crater is 10,000 to 100,000 years
old,? said Dr Hickman.

The crater is 270m across (around the size of the MCG) and is just 35km north of
Newman, but hadn?t been previously discovered.

The area was even mapped by the Geological Survey of WA about 20 years ago, but
the crater went unnoticed.

So could anyone be using Google Earth and find their own meteorite crater?

?Sure,? says Dr Hickman, ?Large meteorites hit every few thousand years, so when
you consider that the landscape is millions of years old, there?s a lot of
potential for meteorite craters out there.?

On a satellite image, meteorite craters are distinguishable from other landforms
because they are almost perfectly circular and have a raised rim.

Dr Hickman said that about 30 per cent of Western Australia is shown in very
high image quality on Google Earth.

The research done by Dr Glickson and his team suggest that the amount of energy
released when the meteorite hit was the equivalent of 200,000 to 300,000 tonnes
of TNT.

The next stage of the geologists? research is to try and find fragments of the
meteorite, a process that is being hindered by the amount of black iron-rich
rock in the vicinity of the crater.
Received on Mon 17 Mar 2008 08:43:59 PM PDT