AW: [meteorite-list] CRE ages of Nakhlites and NWA 998

From: Norbert Classen <trifid_at_meteoritecentral.com>
Date: Sat Nov 11 14:20:24 2006
Message-ID: <000301c705c6$5ff6c5e0$2002a8c0_at_lunatic>

Jerry wrote:

> Help! CRE age??

CRE age = cosmic radiation exposure age. As soon as a chunk of matter has
been released into space from its parent body it gets exposed to the solar
wind and cosmic radiation, and as soon as it lands on our planet the period
of exposure ends. The particles/isotopes implanted by the solar wind and by
cosmic radiation can be measured, and the CRE age can be determined, meaning
the transition time from the meteorite's parent body to Earth, i.e., the
time that it has been actually floating in open space as a meteoroide.

Not to be confused with crystallisation age or terrestrial age...

Hope this helps,
Norbert
Received on Sat 11 Nov 2006 02:19:55 PM PST