Re: [meteorite-list] Chelyabinsk - cosmic-ray exposure age
Or could it be that the radioisotopic chronometer was reset by the second mentioned shock event and the actual cosmic-ray exposure age is much younger? Von: karmaka karmaka-meteori...@t-online.de An: met-list meteorite-list@meteoritecentral.com Betreff: [meteorite-list] Chelyabinsk - cosmic-ray exposure age Datum: Tue, 19 Mar 2013 16:56:40 +0100 Dear list members, according to ITAR-TASS the cosmic-ray exposure or ejection age of Chelyabinsk is reported to be 289 million years, which seems very, very high for a chondrite. Can this be? Are there other chondrites with such a high exposure age or is this a typo and it is rather 28.9 million years? http://translate.google.de/translate?sl=rutl=enjs=nprev=_thl=deie=UTF-8eotf=1u=http%3A%2F%2Fwww.itar-tass.com%2Fc9%2F680067.html What do you think? Martin Postfach fast voll? Jetzt kostenlos E-Mail Adresse @t-online.de sichern und endlich Platz für tausende Mails haben. http://www.t-online.de/email-kostenlos __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list Postfach fast voll? Jetzt kostenlos E-Mail Adresse @t-online.de sichern und endlich Platz für tausende Mails haben. http://www.t-online.de/email-kostenlos __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Chelyabinsk - cosmic-ray exposure age
Hello Martin and List, Martin inquires: according to ITAR-TASS the cosmic-ray exposure ... age of Chelyabinsk is reported to be 289 million years,...is this a typo and it is rather 28.9 million years? That would be my uneducated guess. Here are some CRE ages for LL4 chondrites (Chelyabinsk is an LL4 !) culled from Graf Th. (1994): 07.2 - Sevilla 13.6 - Kelly 15.8 - Benares (a) 17.3 - Savtschenskoje 39.1 - Albareto 40.6 - Hamlet 41.6 - Bo Xian 71.1 - Soko-Banja Reference: GRAF TH. et al. (1994) Collisional records in LL chondrites including noble gas data and exposure ages (Meteoritics 29-5, 1994, 643-648). Cheers, Bernd __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Chelyabinsk - cosmic-ray exposure age
Roman just told me this: Below you write Chelyabinsk is an LL4 ! But the bulletin states LL5. Oops, sorry, ... Roman is absolutel right!!! Bernd __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
[meteorite-list] Chelyabinsk - cosmic-ray exposure age
Me again with the CRE ages of eleven LL5 chondrites from Graf's article in MAPS: 08.4 Olivenza 11.5 Oberlin 13.4 Tuxtuac 13.8 Siena 14.3 Paragould 14.5 Richmond 14.8 Guidder 14.9 Krähenberg 22.6 Altaameem 47.0 Selden 47.7 ALHA78109 Average CRE age of 11 LL5 chondrites = 31.55 Myr Reference: Graf Th. et al. (1994) Collisional records in LL chondrites including noble gas data and exposure ages (Meteoritics 29-5, 1994, 643-648). Cheers, Bernd __ Visit the Archives at http://www.meteorite-list-archives.com Meteorite-list mailing list Meteorite-list@meteoritecentral.com http://six.pairlist.net/mailman/listinfo/meteorite-list
