[meteorite-list] RICHLAND
From: Michael Farmer <meteoriteguy_at_meteoritecentral.com>
Date: Tue, 20 Mar 2007 09:23:01 -0700 (PDT) Message-ID: <177283.92057.qm_at_web33113.mail.mud.yahoo.com> Jeff, Now comes the question of how a large piece of a meteorite came to rest 178 miles (297 km) from the first piece. This meteorite was plowed up in the 1940's, where it had been periodically damaging the farmer's equipment. He finally saw the meteorite that had caused him so much trouble and dug it out. The main mass had numerous plow cuts on it, but I am sure the meteorite dished out far more damage than it received. Does anyone have an explanation as to how or why it could/would be transported so far back then, and buried in a farmers field? I have my doubts that this could be possible. If the natives had taken the trouble to carry it that far (before horses) I doubt they would have cast it off so like junk, it would likely have ended up in a mound or something. Michael Farmer --- Jeff Grossman <jgrossman at usgs.gov> wrote: > First of all, for the many of you without access to > Geochimica et > Cosmochimica Acta, here is the quote from Wasson, > J.T., Huber, H., > and Malvin, D.J. (2007) Formation of IIAB iron > meteorites. GCA 71, 760-781: > > >The 47-kg Fredericksburg (Texas) iron was first > reported > >to us by a person living in Alaska, who stated that > it had > >been inherited from a deceased relative who had > lived near > >Fredericksburg. Our analysis of the sample shows > that, > >within error, its composition is the same as that > of the > >Richland (Texas) iron. Both irons appear to be > strongly > >weathered. However, these two Texas locations are > >297 km apart, farther apart than plausible for a > strewn > >field. Our best guess is that human transport has > been involved, > >and that they are fragments from the same fall > >event. Fredericksburg is not an approved name; we > suggest > >that this mass be referred to as Richland > (Fredericksburg) > >unless future studies imply that it resulted from a > distinct > >fall. > > There are many irons with multiple named masses, > although all of the > masses share the same formal name, in this case > "Richland." For > historical reasons, as well as to recognize to > possibility that > pairings are never 100% certain, the names of the > individual masses > are frequently preserved in catalogs and the > literature, and should > be preserved by dealers and collectors as well. In > this case, > changing the "main mass" designation (which I > consider to be a sloppy > term) doesn't really help the situation. It will > always be better to > refer the new piece as the "Fredericksburg mass of > Richland" or, as > Wasson suggests, the "Richland (Fredericksburg) > mass". > > Another classic example of an iron with multiple > named masses is > North Chile, which includes, among others, the > well-known Filomena > and Tocopilla masses. > > I've now added the Richland synonyms to the MetBull > database. > > Jeff > > At 01:21 AM 3/20/2007, Sterling K. Webb wrote: > >Hi, All, > > > > Strictly as a dumb and innocent bystander on > the > >Thread: Illinois Irons, which is now and forever > more > >shall be about a Texas/Alaska Iron, I have a dumb > >and innocent question (lamb to the slaughter). > > > > Here's what the Catalogue of Meteorites says > >about RICHLAND: > > > >A mass of 30lb (13.6kg) was found when > >an old well was being cleaned out. Listed, > >F.C. Leonard (1956). > > > >Analysis, 5.56 %Ni, E.P. Henderson & > >O.E. Monnig (1957). > > > >It has been suggested that it is a transported > >piece of Coahuila, but is chemically distinct. > >More recent analysis, 5.40 %Ni, 60.6 ppm.Ga, > >182 ppm.Ge, 8.2 ppm.Ir, J.T. Wasson (1974). > > > >Structurally distinct from Coahuila; shock-melted > >troilite, V.F. Buchwald (1975). > > > > Here's my dumb and innocent question: If the > >mass of RICHLAND is 13.6 kilos and the mass of > >(RICHLAND (FREDERICKSBERG) is 47+ kilos, > >and FREDERICKSBERG is a piece of RICHLAND, > >isn't Mike's 47 kilos (you carried it thru the > airport?) > >the Main Mass? > > > > Naive little physicist says if they are two > pieces > >of the same meteoroid that fell at the same time, > the > >biggest piece is the Main Mass, as in, that > corresponds > >to the physical reality. > > > > OK, ready for the beaurocratic axe to fall. > > > > > >Sterling K. Webb > >--------------------------------------------------------------------- > > > >______________________________________________ > >Meteorite-list mailing list > >Meteorite-list at meteoritecentral.com > >http://six.pairlist.net/mailman/listinfo/meteorite-list > > Dr. Jeffrey N. Grossman phone: (703) 648-6184 > US Geological Survey fax: (703) 648-6383 > 954 National Center > Reston, VA 20192, USA > > > ______________________________________________ > Meteorite-list mailing list > Meteorite-list at meteoritecentral.com > http://six.pairlist.net/mailman/listinfo/meteorite-list > Received on Tue 20 Mar 2007 12:23:01 PM PDT |
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