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Faults and stress. Relationship between traction and stress. s yy. s 3. s yx = s yx. s xx. s 1. Faults and stress: traction and stress. Mohr Circle Graphical construction that lets us visualize the relationship between the principal stresses and tractions on a boundary (like a fault).
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Faults and stress GLG510 Advanced Structural Geology
Relationship between traction and stress GLG510 Advanced Structural Geology
syy s3 syx = syx sxx s1 GLG510 Advanced Structural Geology
Faults and stress: traction and stress Mohr Circle Graphical construction that lets us visualize the relationship between the principal stresses and tractions on a boundary (like a fault). • measured positive clockwise from s1 direction clockwise to plane of interest 2q measure positive clockwise from –sn direction on Mohr circle GLG510 Advanced Structural Geology
Faults and stress: traction and stress Equations of the Mohr Circle (also “Cauchy’s equations”) GLG510 Advanced Structural Geology
Faults and stress: traction and stress 90 GLG510 Advanced Structural Geology
Faults and stress: traction and stress GLG510 Advanced Structural Geology
Faults and stress: traction and stress GLG510 Advanced Structural Geology
Faults and stress: traction and stress GLG510 Advanced Structural Geology
Faults and stress: traction and stress 35 GLG510 Advanced Structural Geology
Faults and stress: traction and stress -Davis and Reynolds t = ss GLG510 Advanced Structural Geology
-Engelder, 1993, Stress regimes in the lithosphere, Princeton Univ. Press GLG510 Advanced Structural Geology
Pollard and Fletcher GLG510 Advanced Structural Geology
Coulomb Law of Failure Coulomb equation tc = c + tan fsn Where tc = critical shear stress required for faulting (shear strength) c = cohesive strength tan f = coefficient of internal friction = m GLG510 Advanced Structural Geology
Faults and stress: traction and stress GLG510 Advanced Structural Geology
Practice GLG510 Advanced Structural Geology