[meteorite-list] Slickenside
From: Bernd Pauli HD <bernd.pauli_at_meteoritecentral.com>
Date: Thu Apr 22 09:49:02 2004 Message-ID: <3BAE4D7B.833D4792_at_lehrer1.rz.uni-karlsruhe.de> Charlie wrote: > Can anyone clarify for me the origin of slickenside in meteorites? I > understand the term as it applies to terrestrial soils and sediments. I > have a large individual of Plainview(1917). It's a flat specimen, with > one side fully crusted. The other side looks more like a broken > surface, with crust lipping over the edge from the crusted side. This > "broken" surface is covered with glossy striations in large patches that > I'm assuming is slickenside. What I would like to know is if this > slickenside formed during a tectonic event on the parent body, an impact > event in space, explosive breakup in earth's atmosphere, or other? Hello Charlie and List, All I can contribute is a comment from our former, very competent list member Frank Stroik many years ago: "slickensides are identified by shiny mirror like surfaces on an otherwise rough rock - they are the product of faulting in a rock body; as the crust shifts, even slightly, the roughness of the rock tends to smooth." ... and some meteorites that are reported to exhibit slickensides: Magombedze (H6): In places where the meteorite has been broken exactly along these veins, exposed metal grains are smeared and streaked and show obvious slickensides [MacPHERSON G.J. et al. (1993) Magombedze: A new H chondrite with light-dark structure (Meteoritics 28-1, 1993, 138-142)]. ALHA77225 (H4): The B surface has what appear to be slickensides, but because of the severe weathering of the specimen it is impossible to determine this unambiguously [MARVIN U.B. and MASON B. (1982) Catalog of Meteorites from Victoria Land, Antarctica, 1978-1980 (Smithsonian Contributions 24, p. 23)]. ALHA77254 (L5): The B surface has slickensides [Marvin, U.B. and Mason B. (1980) Catalog of Antarctic Meteorites, 1977-1978, Smithson. Contr. Earth Sci. 23, p.32]. ALHA78108 (H5): Many slickensided surfaces were exposed during processing [MARVIN U.B. and MASON B. (1982) Catalog of Meteorites from Victoria Land, Antarctica, 1978-1980 (Smithson. Contr. 24, p. 28)]. LON 94102 (C2): Slickenside-like features are visible on the surface (Macroscopic Description: Kathleen McBride) > Also, regarding Plainview(1917), can anyone tell me if the newest > edition of the Catalog makes reference to this meteorite being a > possible witnessed fall from 1903(?)? No, Charlie, it doesn't. Best wishes, Bernd Received on Sun 23 Sep 2001 05:00:43 PM PDT |
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