[meteorite-list] Tulia (a)

From: Bernd Pauli HD <bernd.pauli_at_meteoritecentral.com>
Date: Thu Apr 22 09:49:02 2004
Message-ID: <3BAA3F69.BA353218_at_lehrer1.rz.uni-karlsruhe.de>

Martin Horejsi wrote:

> The slice is about 60 grams and the
> inclusion is triangle about 4 mm by 4mm
 
> http://aristotle.isu.edu/tulia_a_inclusion.jpg


Hello Martin, Rhett, and List,

In an 1989 article on carbonaceous material, M.M. Grady
and co-authors state that some of the unequilibrated ordinary
chondrites appear to contain an indigenous organic component
plus show evidence for an amorphous/graphitic component.
The solar-wind gas-rich breccias Dimmitt and Plainview, but
not (yet) Tulia (a), are mentioned as showing C-rich clasts.
In addition, Dimmitt is also reported to contain C-rich
inclusions/aggregates. As a result of TEM studies, this
carbon is described as "highly disordered graphite" that
should be referred to as "poorly-graphitized carbon".
Some of the Ca-rich aggregates in Dimmitt may even
contain pre-solar material.

Now could Martin's 60-gram Tulia (a) be a Dimmitt
because this extraordinary inclusion looks suspiciously
like the clasts described by M.M. Grady et al. ?

I have a very beautiful 11-gram thinly cut Korra Korrabes
slice which also exhibits such a dark, trapezoidal clast
measuring 0.6 x 0.5 x 0.6 x 0.3 cm. It looks like the
arrow-shaped dark inclusion pictured in L. D. Ashwal's*
article in MAPS on page 1030 in the 11 o'clock position.
A very interesting piece that I am very proud of!


* ASHWAL L.D. (2001) Korra Korrabes: A new, large H3 chondrite
   breccia from Namibia (MAPS 36-8, 2001, pp. 1027-1038).


Best wishes,

Bernd
Received on Thu 20 Sep 2001 03:11:37 PM PDT