[meteorite-list] Missouri "Round Rocks" are tektites?

From: Jason Utas <meteoritekid_at_meteoritecentral.com>
Date: Wed, 8 Sep 2010 20:23:36 -0700
Message-ID: <AANLkTi=9rE65nA8VfCRo9p=L_FykWH5HbcXY589FM_c6_at_mail.gmail.com>

Hello Bill, All,
Google-ing "Osceola round rocks" turned up the following:

http://en.wikipedia.org/wiki/Weaubleau-Osceola_structure

Excerpt:

Round rocks of Osceola

Long thought to be a glacial remnant, these?conglomerate rocks?are
found in the area of Osceola. They are nearly perfectly round, and are
referred to locally simply as "round rocks" or "Missouri rock balls".
Current theory suggests that these rocks are?chert?concretions,
created when the impact threw pieces of?shale?away from the center of
the crater, and later silica-rich materials formed around the shale
seeds.

The following reference mentioned the round rocks, but gave no
explanation for their formation:

http://courses.missouristate.edu/KevinEvans/RI-75(2003AMGguidebook).pdf

The next reference noted 'angular' chert clasts with siltstone
interiors, but made no mention of the rounded cobbles:

http://www.lpi.usra.edu/meetings/largeimpacts2003/pdf/4111.pdf

The amount of information you can find in only a few minutes with a
simple search...that internet's an amazing thing.
Best,
Jason

On Tue, Sep 7, 2010 at 4:10 PM, bill kies <parkforestmet at hotmail.com> wrote:
>
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Received on Wed 08 Sep 2010 11:23:36 PM PDT