[meteorite-list] Found 20 km apart - just what does "pairing" really mean?

From: Nick Gessler <gessler_at_meteoritecentral.com>
Date: Thu Apr 22 09:44:30 2004
Message-ID: <5.0.2.1.0.20010228173808.01cb20d0_at_pop.bol.ucla.edu>

Hellolist,

I would sure like to second Bob's remarks. Proximity means diddlely to
me. As far as I'm concerned there are only three valid tests for pairing:
1) physical pairing - the pieces fit together (the most certain)
2) taxonomic pairing - the pieces yield the identical analysis (a bit less
certain)
3) statistical pairing - odds are the pieces came from the same source (but
be prepared to show me ample data of what fell where)

I personally have fitted dozens of fragments together to reconstruct larger
bodies that entered the atmosphere together. Folks get a good laugh from
this, but with my background as an archaeologist who has glued many pot
sherds together, what can you expect?

Those of us who have worked the California deserts know that "strewn
fields" (ellipses of deposition) may or may not represent "discovery
fields" (ellipses of recovery). We have found taxonomically different
individuals an arm's length from one another. And we have found "fields"
or ellipses which contain dozens of different taxonomic types. In fact,
the closer we look, the more types we find.

Even when two specimens are taxonomically paired, it can be shown
statistically that when you find a half-a-dozen distinctly different
taxonomically types in a "field," this almost guarantees that many of the
most common taxonomic "pairings" in that same area, taxonomically
identical, will undoubtedly be from different falls.

Thanks Bob, for bringing this up...

Nick
Received on Wed 28 Feb 2001 08:52:30 PM PST