[meteorite-list] AD - Do you want a rareandimportantMetachondrite?

From: stan . <laser_maniac_at_meteoritecentral.com>
Date: Wed Sep 28 21:27:36 2005
Message-ID: <BAY101-F41ADA222E9E8F893FE0719F08C0_at_phx.gbl>

>This is interesting as I've never heard this before. Can terrestrial
>weathering really have a significant effect on oxygen results?

yup - oxygen isotopse analysis basically involves vaporizing a bit of the
meteorite with a laser in a strongly oxydyzing environment - normally
flourine. basically all atomic bonds between atoms int he meteorite are
broken down int he vaporized bit freeing up any of the chemically
sequestered oxygen. the flourine atmosphere is present to latch on to
anything that would otherwise want to bond back with the now free oxygen.
the resulting minute gas sample is sent trought a series of filters to
remove these products adn the oxygen then goes to a mass spectrometer to
identify the ratio between the various isotopse present. any terrestrial
source of oxygen such as calcium carbonate will therefore alter the ratio of
the isotopse present.
Received on Wed 28 Sep 2005 09:27:32 PM PDT