[meteorite-list] Impact Melt meteorites

From: Bernd Pauli HD <bernd.pauli_at_meteoritecentral.com>
Date: Thu Apr 22 09:47:13 2004
Message-ID: <3BFEAA1D.47E352C2_at_lehrer1.rz.uni-karlsruhe.de>

Rhett Bourland wrote:

> ... aren't lodranites impact melted acapulcoites? *

McCoy et al. write that there are those lodranites that could be
derived from partial melting and reduction of a common precursor
(eg., acapulcoites *). But the authors also say that "some evidence
is inconsistent with this interpretation. And there are the iron-rich
lodranites which cannot be produced by partial melting of an acapul-
coite precursor. [McCOY T.J. et al. (1992) Petrogenesis of the
Lodranite- Acapulcoite parent body (Meteoritics 27-3, 1992, A258)].

Now, as for impact melts:

McCOY T.J. et al. (1996) A petrologic, chemical, and isotopic study
of Monument Draw and comparison with other acapulcoites: Evidence
for formation by incipient partial melting (GCA 60, 2681- 2708):
In that paper McCoy et al. conclude that acapulcoites formed by
n o n c o l l i s i o n a l heating to temperatures of ~950-1000*C
of chondrite precursor material unlike.

I would interpret the word "noncollisional" to imply that
they are not i m p a c t melts but I may be mistaken.


Best wishes,

Bernd
Received on Fri 23 Nov 2001 02:57:17 PM PST