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View Full Version : Why no old tektites?



Tom Mazanec
2016-Feb-09, 02:56 PM
The Wikipedia gives ages of five likely tektite fields to ~775,000 years (Australasian), 15,000,000 years (Europe), 1,000,000 years (Ivory Coast), 34,000,000 years (North American) and 820,000 years (Central American possible).
Even the oldest is less than one percent the Earth's Age.
Three of the fields are in the last few percent of the "Age of Tektites".
Why the recency?

grapes
2016-Feb-09, 04:29 PM
"Microtektites" seem to go much further back. Perhaps the larger specimens are too delicate to last long.

http://www.ncbi.nlm.nih.gov/pubmed/17840279

John Mendenhall
2016-Feb-09, 05:29 PM
"Microtektites" seem to go much further back. Perhaps the larger specimens are too delicate to last long.

http://www.ncbi.nlm.nih.gov/pubmed/17840279

IIRC, tektites are not stable over geologic time. They are a glass, and again, IIRC, that is generally true of glasses.