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microtektites
- To: meteorite-list@meteoritecentral.com
- Subject: microtektites
- From: Guy Heinen <guy.heinen@ci.educ.lu>
- Date: Sat, 21 Feb 1998 09:04:40 +0100
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Microtektites accompanying the North American event (34.2 +- 2.0 million
years ago)have been found in the Gulf of Mexico,near the coasts of New
Jersey (Deep Sea Drilling Project 612)and near Bath Cliff (Barbados).
The microtektites from Haiti are correlated to the K/T-boundary event.They
are 'fossilized':the outer parts are changed into smectite (Na,Ca)0.3
(Al,Mg)2 (OH2/Si4O10).4H2O.
Other microtektite-like spheres have been found in Belgium.Age:367 million
years,late Devonian,Frasnian-Famennian boundary.
Other microspheres are marking the Precambrian-Cambrian boundary (-570
million years)and were found in China (Meishucun).
The Permian-Triassic boundary is marked with microspheres in South China
(Meishan).
The Acraman impact in South Australia (-592 million years)has produced an
ejecta blanket containing microspheres.
All those above-mentioned microspheres MAY have been
microtektites,today,glass is replaced by minerals.