[meteorite-list] CV3 subtypes revised

From: David Weir <dgweir_at_meteoritecentral.com>
Date: Thu Apr 22 10:32:52 2004
Message-ID: <405C651C.419EBF60_at_earthlink.net>

Hello List,

http://www.lpi.usra.edu/meetings/lpsc2004/pdf/1562.pdf

I've read through many of the LPSC abstracts and this one seems to be
significant in that it suggests a reconsideration of the subtypes of
many CV3s. The authors utilized several methods to determine the
subtypes of CV3 chondrites; Raman spectometry of organic material, a
petrologic study of Fe zoning, and a noble gas study, rather than the TL
sensitivity data of feldspar typically used for ordinary chondrite
subtyping, and which was previously applied to the CV3s. They propose
that TL sensitivity data is not applicable to aqueously altered CCs and
they have redefined the petrographic subtypes of the common CV3s as
follows:

Allende - >3.6 (TL - 3.2)
Axtell - >3.6 (TL - 3.0)
Grosnaja - ~3.6 (TL - 3.3)
Kaba - 3.1 (TL - 3.0)
Mokoia - ~3.6 (TL - 3.2)
Bali - >3.6 (TL - 3.0)
Efremovka - 3.4-3.6 (TL - 3.2)
Vigarano - 3.1-3.4 (TL - 3.3)
Leoville - 3.1-3.4 (TL - 3.0)

They plan to make further studies to validate this one.

David
Received on Sat 20 Mar 2004 10:37:00 AM PST