[meteorite-list] Seymchan Pallasite

From: Matt Morgan <mmorgan_at_meteoritecentral.com>
Date: Mon Sep 20 15:23:55 2004
Message-ID: <002601c49f47$516ed950$6400a8c0_at_D14191145L2K>

>From what Serge told me, only a small piece of the original iron was
analyzed; therefore, the olivines were probably missed. Many of the
slabs contain regions completely devoid of olivine, these remind me of
the Glorieta and Brenham masses in appearance. The etch of these do not
look like Brahin. So I do not think that is it. Plus Serge is an honest
man and showed me where these pieces were found.
Matt

-----Original Message-----
From: meteorite-list-bounces_at_meteoritecentral.com
[mailto:meteorite-list-bounces_at_meteoritecentral.com] On Behalf Of J?rn
Koblitz
Sent: Monday, September 20, 2004 6:12 AM
To: mark ford; Meteorite List
Subject: AW: [meteorite-list] Seymchan Pallasite


Hello Mark and List,

here is an extract from MetBase on Seymchan:

-------------------------------------------------------
A mass of 272.3kg was found in the bed of a stream flowing into the
river Hekandue, a tributary of the Jasachnaja, a second mass of 51kg was
later found at a distance of 20 m from the first one, Met. Bull. 42, 43,
Meteoritics, 1970, 5, p.97; see also, A.L.Graham et al., Cat. Met.,
1985, p.323. The coordinates are of the town of Seymchan. Find
circumstances, V.I.Tsvetkov, Meteoritika, 1969, 29, p.152. Illustrated
description, with an analysis, 9.47% Ni, O.A.Kirova and M.I.Dyakonova,
Meteoritika, 1972, 31, p.104. Further analysis, 9.15% Ni, 24.6 ppm Ga,
68.3 ppm Ge, 0.55 ppm Ir, E.R.D.Scott and J.T.Wasson, GCA, 1976, 40,
p.103. Further INAA data, previously classified into the IIE group, but
now designated ungrouped based on the chemical composition, J.T.Wasson
and J.Wang, GCA, 1986, 50, p.725. Another analysis, A.N.Krot et al.,
Meteoritics, 1992, 27, p.465. Nitrogen isotopic composition, R.L.Palma
et al., LPSC, 1997, 28, p.1057 (abs.); see also, K.Marti et al., MAPS,
1997, 32, p.A84 (abs.); K.J.Mathew et al., GCA, 2000, 64, p.545.
-------------------------------------------------------

Acording to the more recent analysis by Wasson and Chang (1986), the
metal of Seymchan is ungrouped, thus cannot be related to - at least -
the main-group pallasites (e.g. Brenham, Esquel, Imilac) which are
genetically linked to IIIAB irons.

So, may be we have a new kind of pallasite here (exotic like e.g. Eagle
Station)!

On the other hand, rounded silicate inclusions are commonly found in IIE
irons like Miles, Elga, or Kodaikanal. Thus, it is well possible to mix
such silicated irons up with pallasites and Seymchan is actually an
ungrouped silicated iron.

Best regards,
J?rn

________________________________________________________________________
_______
Joern Koblitz
MetBase Editor
The MetBase Library of Meteoritics and Planetary Sciences Benquestrasse
27 D-28209 Bremen, Germany
phone: +49 421 24 100 24
fax: +49 421 168 2799
email: info_at_metbase.de
________________________________________________________________________
_______

 


> -----Urspr?ngliche Nachricht-----
> Von: mark ford [mailto:markf_at_ssl.gb.com]
> Gesendet: Montag, 20. September 2004 10:54
> An: Meteorite List
> Betreff: RE: [meteorite-list] Seymchan Pallasite
>
>
>
> Hi,
>
> Anyone got a link to any classification details for this seymchan
> pallasite?
>
> Looks quite interesting, very sharp Olivine pieces....
>
> Best
> Mark
> ______________________________________________
> Meteorite-list mailing list Meteorite-list_at_meteoritecentral.com
> http://six.pairlist.net/mailman/listinfo/meteorite-list
>
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Received on Mon 20 Sep 2004 03:23:30 PM PDT