1. GLG310 Structural Geology

2. 21 December 2015GLG310 Structural Geology

3.  d is differential stress -Engelder, 1993, Stress regimes in the lithosphere, Princeton Univ. Press

4. 21 December 2015GLG510 Advanced Structural Geology Rheology: “science of deformation and flow of matter” or relationship between stress and strain

5. Idealized Elastic Material Linear relationship between force and extension (Hooke, 1676): Ut tensio sic uis As extension so the force Analogous to spring constant http://www.see.leeds.ac.uk/structure /rheology/hooke.htm

6. GLG310 Structural Geology

7. 21 December 2015GLG510 Advanced Structural Geology E (young’s modulus) = d  a /d e a Units of stress -Pollard and Fletcher, 2005

8. 21 December 2015GLG310 Structural Geology http://silver.neep.wisc.edu/~lakes/PoissonIntro.html

9. 21 December 2015GLG510 Advanced Structural Geology  a = f/A e a = (b-B)/B  p = 0 e p = (w-W)/W = - e p / e a (Poisson ratio) Measures compressibility Axial versus transverse deformation

10. Idealized Elastic Material

11. 21 December 2015GLG510 Advanced Structural Geology Stiffness and strength “Lest there be any possible, probably, shadow of doubt, strength is not, repeat not, the same thing as stiffness. Stiffness, or Young’s modulus or E, is concerned with how stiff, flexible, springy or floppy a material is. Strength is the force or stress needed to break a thing. A biscuit is stiff but weak, steel is stiff and strong, nylon is flexible (low E and strong), raspberry jelly is flexible (low E) and weak. The two properties together describe a solid about as well as you can reasonably expect two figures to do.” (Gordon, New science of strong materials, 2006)

12. http://www.see.leeds.ac.uk/structure/rhe ology/inelastic.htm

13. Plasticity Steady deformation at yield strength

14. Plasticity Steady deformation at yield strength

15. 21 December 2015GLG510 Advanced Structural Geology Viscosity Strain rate proportional to differential stress

16. 21 December 2015GLG310 Structural Geology

17. 21 December 2015GLG310 Structural Geology http://www.youtube.com/watch?v=GxdfoJoWNE4 Variations in mechanical behavior

18. 21 December 2015GLG310 Structural Geology Rock deformation experiments

19. 21 December 2015GLG310 Structural Geology

22. http://www.cast.com.sg/s_soil.html

24. 21 December 2015GLG310 Structural Geology http://www.youtube.com/watch?v=n4ZAb-p-dIw

25. http://maydamedia.com/Images/Chapter11/Chart11.1.jpg Rocks can flow: salt ascends through overlying sediments because it is bouyant

26. 21 December 2015GLG310 Structural Geology