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Post Info TOPIC: Australites


L

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RE: Australites
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A better picture and a better location....

145.65883E_42.30483S

Latitude = -42.30483 Longitude = 145.65883

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L

Posts: 131433
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Darwin Crater
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darwincratermap
Locations where Darwin glass has been found.




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L

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Darwin Crater was discovered in 1972 by Ramsay J. Ford. The crater lies 26 km south of Queenstown Tasmania.
The crater was formed by a 20 - 50 m diameter asteroid struck the Earth approximately 730,000 +/- 40,000 years ago.
The crater has a diameter of 1.2km and is 230 metres deep. It was a lake until about 30 000 years ago, today it is filled with sediment.
The crater is associated with an extensive silica glassfields.
Molten rock ejected from the crater covers more than 400 km of western Tasmania.


Position: 42°18.39'S, 145°39.41'E

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L

Posts: 131433
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Australites
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Where is the Crater that formed the Australian tektites?
No crater has been found...
Australites (and Indochinites which are indistinguishable from each other) have been dated to about 710,000 years using fission track and potassium-argon (K-Ar) dating methods; However the stratigraphic positions indicates an age of 7000 to 20,000 years BP.
From their chemical composition, both belong to the same impact event...!

The evidence seems to show a least two episodes of australite falls - one relatively recent (24,000 and 16,000 years ago) and at 710,000years. This may be due to un-natural sorting by early man in Australia. Australites are unusual in that some show that they were remelted.. this may show different trajectories - sending some material into orbit...

Darwin glass from South West Tasmania has a combined K-Ar and fission track age of 730,000 ±40,000 years. It seems that Darwin crater was perhaps the source of both.
It is possible that the impact crater may be part of two or more events that occurred together. Another associated impact crater could have formed in the Indonesian region. As yet that larger impact crater that still has to be found...

Darwin Crater has a diameter of 1 km


(At first i thought this was a possible location )
Position: -42.249599° 145.555629°

-- Edited by Blobrana at 23:41, 2006-05-27

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