[meteorite-list] Meteorite Question

From: Bernd Pauli HD <bernd.pauli_at_meteoritecentral.com>
Date: Thu Apr 22 10:00:06 2004
Message-ID: <3D306A50.3DDADD63_at_lehrer.uni-karlsruhe.de>

Pierre Rochette a écrit:

> the inference "this is an anomalous meteorite" should
> not be put forward before answering the questions: ...

Bonjour Pierre, hello List,

I absolutely concur and that's why I cautiously spoke of "exceptions
to the rule" instead of using a designation like "anomalous meteorite".

> excluding type 3, finds and incompletely classified meteorites and allowing
> for a half percent error leave practically no anomalies in Bernd's list!

Right on target again! By the way, today I received an email from the
Sahara Team (Richard & Roland Pélisson), informing me about the range
of fayalite in the DaG 862 (main mass in their possession). The range
is:

Olivine Fa14.4 (0.33-32.29); pyroxene Fs13.1 (1.09-32.21)

Of course, I shouldn't have included this meteorite in
my overview as it is an unequilibrated H3 chondrite!

> By the way why is Burnwell not fully classified?

Burnwell has not yet been definitely classified or
grouped because of some exotic characteristics:

- lower Fa in olivine
- lower Fs in orthopyroxene
- lower Co in kamacite
- lower FeO in the bulk chemical analysis
- lower D17O than other equilibrated OC's
- ordinary chondrites
- higher Fe,Ni metal than other H chondrites

Thus, some meteoriticists postulated an "HH" classification but
Russell S.S. et al. (1998)are hesitant since this would imply
a genetic significance that has not yet been fully ascertained.
They use the term "low-FeO chondrite" instead to describe the
Burnwell meteorite.

Reference:

RUSSELL S.S., McCOY T.J., JAROSEWICH E. and ASH R.D. (1998)
The Burnwell, Kentucky, low iron oxide chondrite fall: Description,
classification and origin (Meteoritics 33-4, 1998, 853-856).


Best regards,

Bernd
Received on Sat 13 Jul 2002 01:58:40 PM PDT