[meteorite-list] The San Pedro de Urabá meteorite fall is approved (Feb 16, 2017, Colombia)

From: Galactic Stone & Ironworks <meteoritemike_at_meteoritecentral.com>
Date: Fri, 8 Jun 2018 15:45:05 -0400
Message-ID: <CAKBPJW9XkKz7-bgLvrVwjxMi3VzmikjJfvMgY5iW4JJ8-vJ08A_at_mail.gmail.com>

The San Pedro de Urab? meteorite fall from February 2017 has been
approved and published in the Met Bulletin :

San Pedro de Urab?
8?16?44.39"N, 76?22?41.67"W
Antioquia, Colombia
Confirmed fall: 16 Feb 2017
Classification: Ordinary chondrite (L6)

History: At 5:30 pm local time on 16 February 2017, a large fireball
with sonic booms was observed in northern Colombia. A meteorite
subsequently impacted near Mr. Orlando Cuevas on the edge of a soccer
field in San Pedro de Urab?, Turbo district, Antioquia State,
Colombia. The event was widely reported in the local media. Two other
stones are known to have fallen, one much larger than the one that was
collected in the soccer field, but their whereabouts are unknown.
Michael Farmer acquired the 3768 g stone from Mr. Cuevas.

Physical characteristics: Single regmaglypted stone covered with matte
black fusion crust. Interior is a light greenish-gray and friable. Cut
surface shows poorly defined chondrules and even distribution of small
metal/troilite grains. Only a single thin shock vein is visible.

Petrography: SEM observation of a polished mount shows scattered
poorly defined chondrules (BO, RP, and PO) largely integrated with the
matrix. All silicates heavily fractured. Feldspar grains typically >50
?m, with many around 100 to 200 ?m. Troilite anhedral and dominantly
single crystal to 400 ?m. Rare anhedral Ca-Na-Mg phosphates to 60 ?m.
Chromite to 600 ?m is anhedral to subhedral and heavily fractured.
Three Fe-Ni metal types present: kamacite, dominantly single crystal
(to 0.5 mm) with a frosty etch and weakly defined Neumann bands;
tetrataenite, rare, commonly contiguous to kamacite; and, equant
Ni-zoned grains with Ni-rich rims and dark-etched cores, some showing
kamacite spindles. Native Cu is rare and occurs as <10 micron grains
at kamacite/troilite boundary. Scattered and rare melt pockets to 60
?m.

Geochemistry: Olivine Fa25.1?0.3, FeO/MnO=47.6?1.8, n=9; low Ca
pyroxene Fs21.4?1.2Wo1.5?0.2, FeO/MnO=28.4?1.3, n=10; Feldspars
Or13.4?0.3Ab67.3?67.3?0.5, n=3 and Or5.4?0.1Ab84.4?0.02, n=2.

Classification: Ordinary chondrite L6, S3, W0

Specimens: 32 g at ASU. Main mass with MFarmer.

Link - https://www.lpi.usra.edu/meteor/metbull.php?code=67598

21st Century Witnessed Falls - http://galactic-stone.com/pages/falls

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Received on Fri 08 Jun 2018 03:45:05 PM PDT