1 / 42

Geology 3120 - Introduction to Strike-Slip Faults

Geology 3120 - Introduction to Strike-Slip Faults. Levant Strike-Slip Faults. Outline. Stick-Slip and Creep Andersonian Theory Kinematics Strike-Slip Faults on Continental Margins Strike-Slip Faults on Mid-Ocean Ridges. Stick-Slip: Elastic Rebound Theory. D. Elastic Rebound Theory.

ataret
Télécharger la présentation

Geology 3120 - Introduction to Strike-Slip Faults

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Geology 3120 - Introduction to Strike-Slip Faults

  2. Levant Strike-Slip Faults

  3. Outline • Stick-Slip and Creep • Andersonian Theory • Kinematics • Strike-Slip Faults on Continental Margins • Strike-Slip Faults on Mid-Ocean Ridges

  4. Stick-Slip: Elastic Rebound Theory D

  5. Elastic Rebound Theory • Imagine a fence across an active fault

  6. Elastic Rebound Theory • Imagine a fence across an active fault • Regional deformation occurs but the fault does not break. The fence becomes curved.

  7. Elastic Rebound Theory • Imagine a fence across an active fault • Regional deformation occurs but the fault does not break. • Once the fault breaks, the fence is sheared in half and marks offset • Note that far-field strain may limit whether the fault accommodates all the plate motion at its trace

  8. Elastic Rebound Theory

  9. Elastic Rebound Theory

  10. Creep (Aseismic Slip) • Imagine a fence across an active fault • Slip occurs slowly on the fault continually over time. • Creeping faults do not store elastic energy that might be released by a stick-slip event (an earthquake)

  11. Andersonian Theory

  12. Conjugate Strike-Slip Faults

  13. Determining Sense of Slip

  14. Right-Lateral (Dextral)

  15. Left-Lateral (Sinistral)

  16. Arrow Heads ( ) and Tails ( ) Block moving toward you like an arrowhead heading towards you Block moving away from you like seeing the feathers of an arrow

  17. Arrow Heads ( ) and Tails ( ) Right-lateral or left-lateral?

  18. Arrow Heads ( ) and Tails ( ) Left-lateral

  19. Arrow Heads ( ) and Tails ( ) Sinistral or Dextral?

  20. Arrow Heads ( ) and Tails ( ) Dextral

  21. Strike-Slip Faulting: Shallow Brittle vs Deep Shear

  22. Strike-Slip Faulting: EQ’s = dislocations See http://www.data.scec.org/Module/links/landrupt.html Landers rupture propagation movies

  23. Strike-Slip Faults on Continental Margins 50 m N What is the sense of slip?

  24. Strike-Slip Faults on Continental Margins 50 m N Right-lateral (dextral)

  25. Transtension

  26. Development of a Pull-Apart Basin

  27. Pull-Apart Basin

  28. Initial Releasing Bend

  29. Evolution of a Releasing Bend

  30. Normal (-) Flower Structure - Tulip

  31. Transpression

  32. Development of a Restraining Bend

  33. Initial Restraining Bend

  34. Evolution of a Restraining Bend

  35. Reverse (+) Flower Structure - Palm

  36. Summary of Flower Structures - Palms & Tulips

  37. Oceanic Strike Slip fault: Transforms

  38. Strike-Slip Faults on Mid-Ocean Ridges What is the sense of slip?

  39. Strike-Slip Faults on Mid-Ocean Ridges Right-lateral (Dextral)

  40. Pacific-Antarctic Ridge Magnetic anomalies from present to 9.9 Ma Warm colors indicate positive polarity Cool colors indicate reverse polarity

More Related