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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

SAFOD: hole and core

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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

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31 October 2013 GLG310 Structural Geology

http://en.wikipedia.org/wiki/Mylonite http://upload.wikimedia.org/wikipedia/commons/1/1e/Mylonite_Strona.jpg

http://upload.wikimedia.org/wikipedia/commons/c/cd/Ska%C5%82a_zmyllonityzowana.jpg