[meteorite-list] Geno-, mono-, polymict, and xenolithic -- Part 1 of 3

From: bernd.pauli_at_paulinet.de <bernd.pauli_at_meteoritecentral.com>
Date: Mon Jul 11 14:55:41 2005
Message-ID: <DIIE.0000002700003A84_at_paulinet.de>

Breccia

WASSON J.T. (1974) Meteorites Classification and Properties
(Springer-Verlag, Berlin, Heidelberg, New York, Appendix I,
Glossary, p. 242):

A fragmental rock type including components (the larger pieces called
xenoliths or clasts) which were previously part of another rock. In a
monomict breccia all components originated in the same rock; in a geno-
mict breccia the components originated in distinct but genetically close-
ly related rocks; in polymict breccias the components originated in two
or more unrelated rocks.

NORTON O. R. (2002) The Cambridge Encyclopedia of Meteorites,
Glossary, pp. 343, 344, 345, 347:

genomict breccia: a brecciated meteorite in which the individual clasts
are compositionally of the same group but have differing petrographic
characteristics.

monomict breccia: a brecciated meteorite composed of angular fragments
and matrix all of like composition.

polymict breccia: a rock made up of angular fragments or clasts from other
rocks of different compositions.

xenolith: an inclusion of a foreign rock in an igneous host rock that is not
chemically related to the host rock.
Received on Mon 11 Jul 2005 02:55:40 PM PDT