glg310 structural geology - arizona state...
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GLG310 Structural Geology
Physical character of faults
31 October 2013 GLG310 Structural Geology http://geolmag.geoscienceworld.org/content/145/3/435/F3.expansion
http://www.photoree.com/photos/permalink/891384-19756080@N00
http://www.gm.univ-montp2.fr/spip/spip.php?article761
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Fault surfaces
31 October 2013 GLG310 Structural Geology
http://homepage.usask.ca/~mjr347/prog/geoe118/geoe118.052.html
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Physical character of faults
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http://homepage.usask.ca/~mjr347/prog/geoe118/geoe118.052.html
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Breccia
Photomicrograph of fault breccia in the Antietam Formation, Blue Ridge province. Breccias form
when rocks are extensively fractured in fault zones and are cemented together when minerals
precipitate in the cracks and fractures. Note the angular fragments (fr) of quartz sandstone in a
matrix of fine-grained iron oxide cement (ic). Field of View 4 x 2.7 mm, Cross Polarized Light.
http://web.wm.edu/geology/virginia/provinces/Blueridge/fault_zone_lithology.html
Woodcock and Mort, 2008
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31 October 2013 http://www.webpages.uidaho.edu/~simkat/geol345_files/2012lecture9.html
31 October 2013 GLG310 Structural Geology http://www.carmeliet.arch.ethz.ch/People/Ferdowsi
Gouge along fault zone is more easily eroded
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31 October 2013 GLG310 Structural Geology
http://www.gm.univ-montp2.fr/spip/spip.php?article761
The word "pseudotachylite" was
coined early in the 1900s to name a
peculiar glassy rock that looks sort
of like tachylite but isn't. Tachylite
("TAK-a-lite") is a basaltic glass
A psuedotachylite is a
frictionally generated melt rock
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31 October 2013 GLG310 Structural Geology
http://www4.nau.edu/meteorite/meteorite/book-glossaryp.html
A psuedotachylite is a frictionally generated melt rock
--formed by fault slip, but also impacts
31 October 2013 GLG310 Structural Geology http://maps.unomaha.edu/maher/GEOL3300/week10/dsz.html
Mylonite is a rock formed during
shear with ductile mineral
behavior (quartz), grainsize
reduction (feldspar), and some
grain growth