today’s plan - arizona state...
TRANSCRIPT
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GLG310 Structural Geology
Today’s plan
• Continue Force, Stress, and Strength
(Chapter 3) [continue reading Chapter 3]
• Be sure to cross reference the lecture and
the textbook
• Stretch a bit into faults and stress
26 September 2013 GLG310 Structural Geology
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Classification of
faults
26 September 2013
Fracture
26 September 2013 GLG310 Structural Geology
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26 September 2013
Andersonian Faulting
Theory
• Key assumptions:
– Earth’s surface is a free surface (so it has no
shear tractions acting along it). Therefore, s1,
s2, s3 must be either parallel or perpendicular
to it.
– A fault will slip in the direction of maximum
resolved shear traction
By E. M. Anderson
(1st ed. 1942, 2nd ed. 1951)
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Andersonian Faulting
Theory
26 September 2013 GLG510 Advanced Structural
Geology
Andersonian
Faulting
Theory
Rowland and
Duebendorfer
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Andersonian Faulting
Theory
-Engelder, 1993, Stress regimes in the lithosphere, Princeton Univ. Press
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26 September 2013 GLG310 Structural Geology
Relative stress magnitudes and faulting regimes
(from Reservoir Geomechanics by Zoback--http://www.amazon.com/Reservoir-
Geomechanics-Mark-D-Zoback/dp/0521770696)
26 September 2013
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26 September 2013
World Stress Map
http://www.world-stress-map.org/
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North America Stress Map
http://www.world-stress-map.org/