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Post Info TOPIC: Timor Sea Crater


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Timor Sea Crater
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North Bonaparte Basin


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L

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North Bonaparte Basin
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Title: Origin of the Timor Sea Late Eocene-Pre-Miocene Strewn Crater Field
Authors: J.D. Gorter and A.Y. Glikson

Since the majority of extraterrestrial impacts impinge on oceanic regimes, the identification of buried submarine impact structures from geophysical data, including 3D reflection seismic profiles, constitutes an essential step in unravelling the terrestrial impact record.
However, the method suffers from severe difficulties inherent in the limitations on the amount of drilling and thus the on tests of candidate geophysical features and potential impact structures.
In the Timor Sea, north Bonaparte Gulf, Deep sea drilling and seismic reflection data encounter an at least 350 m-thick PGE-rich radioactive carbonate breccia lens at Fohn-1 exploration well (Gorter and Glikson, 2000).
The data are interpreted in terms of a buried 4.8 km-diameter impact crater of late Eocene to pre-Miocene age. The crater displays the classic elements of impact structures, including a central uplift and ring syncline. The presence in the breccia of redeposited Campanian and Maastrichtian microfossils suggests rebound of strata from levels deeper than 1250 m below the pre-Langhian unconformity. Morphometric modelling suggests an original transient crater depth at least 1400 m deep, consistent with the excavation of Cretaceous strata. Stratigraphic and palaeontological evidence suggests that the impact occurred between 38 and 24 Ma. The breccia contains altered glass components enriched in the inert platinum group elements (PGE) (Ir, Ru) by factors of 5-12 above the values of common sediments. The more mobile PGE (Os, Pt, Pd) show a wide scatter and terrestrial-type values.

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North Bonaparte Basin


Latitude: 1215'21.49"S, Longitude: 12832'1.33"E

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L

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Mount Ashmore dome
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Scientists from The Australian National University have identified a dome at least 50 kilometres in diameter, buried under the Timor Sea that was created by a giant asteroid that collided with Earth around 35 million years ago - a period of heavy extraterrestrial bombardment.
Their findings, which could suggest a link between these impacts and a sharp fall in global temperatures preceding the formation of the Antarctic ice sheet, have been published in the new issue of the Australian Journal of Earth Sciences.

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L

Posts: 131433
Date:
Timor Sea Crater
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Australian scientists have discovered a crater deep beneath the Timor Sea made during a heavy meteor storm which may have altered the Earth's climate, the lead researcher said Thursday.
Australian National University archaeologist Andrew Glikson said seismic activity led experts to the Mount Ashmore 1B site, and a study of fragments showed a large meteorite hit just before the Earth's temperatures plunged.

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