[meteorite-list] Millbillillie vs Allende ages

From: bernd.pauli_at_paulinet.de <bernd.pauli_at_meteoritecentral.com>
Date: Thu Apr 22 10:25:41 2004
Message-ID: <DIIE.0000006100000A8A_at_paulinet.de>

> Hullo,

Hello Dave and List,

> Millbillillie is from a differentiated body I just wondered if it was that
> much younger (say 4.4Gy) as there had to be an elapsed time for the
> formation of the eucritic parent body (Vesta, as presently received)?

Here is some information from an article by Yamaguchi:

YAMAGUCHI A. et al. (1994) Textural variations and impact
history of the Millbillillie eucrite (Meteoritics 29, 237-245):

In table 4, page 244, Yamaguchi et al. present a chronological scenario
concerning the formation of five classified lithologies of the Millbillillie
eucrite.

Stage #1: primary crystallization age of eucrites in general ~4.46-4.56 Ga

Stage #2: Impact (brecciation, melting, mixing, deposition)

Stage #3: Thermal annealing - Granoblastic matrix (3.55 Ga ?)

Stage #4: Impact - Glassy veins (3.55 Ga ?)

Stage #5: Impact - Microcracks


Best regards,

Bernd

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Received on Mon 19 May 2003 11:21:42 AM PDT