1 / 51

Geology 360 - Introduction to Strike-Slip Faults

Geology 360 - Introduction to Strike-Slip Faults. Levant Strike-Slip Faults. Left-lateral strike-slip Levant fault, plate boundary between Arabia and Africa. San Andreas from Space. Two northwest-southeast-trending faults are visible.

wattan
Download Presentation

Geology 360 - 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 360 - Introduction to Strike-Slip Faults

  2. Levant Strike-Slip Faults Left-lateral strike-slip Levant fault, plate boundary between Arabia and Africa

  3. San Andreas from Space • Two northwest-southeast-trending faults are visible. • The Hayward Fault, bordering the urban area east of San Francisco Bay • The San Andreas Fault, crossing the mid-San Francisco Peninsula before dipping beneath the Pacific Ocean and surfacing again northwest of Golden Gate Bridge San Francisco Bay, California.

  4. San Andreas fault, western North America

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

  6. Stick-Slip: Elastic Rebound Theory D

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

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

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

  10. Elastic Rebound Theory

  11. Elastic Rebound Theory

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

  13. Andersonian Theory

  14. Conjugate Strike-Slip Faults

  15. Determining Sense of Slip

  16. Right-Lateral (Dextral)

  17. Left-Lateral (Sinistral)

  18. 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

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

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

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

  22. Arrow Heads ( ) and Tails ( ) Dextral

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

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

  25. Strike-Slip Faulting: EQ’s = dislocations

  26. Strike-Slip Faulting: EQ’s = dislocations

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

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

  29. Transtension

  30. Development of a Pull-Apart Basin

  31. Pull-Apart Basin

  32. Initial Releasing Bend

  33. Evolution of a Releasing Bend

  34. Normal (-) Flower Structure - Tulip

  35. Transpression

  36. Development of a Restraining Bend

  37. Development of a Restraining Bend

  38. Initial Restraining Bend

  39. Evolution of a Restraining Bend

  40. Reverse (+) Flower Structure - Palm

  41. Summary of Flower Structures - Palms & Tulips

  42. Summary of Step Overs - Strike-Slip Faults

  43. Los Angeles - Pull apart structure Releasing bend

  44. Summary of Flower Structures - Palms & Tulips

  45. Summary of Flower Structures - Palms & Tulips

  46. Summary of Flower Structures - Palms & Tulips

  47. Summary of Flower Structures - Palms & Tulips

  48. Oceanic Strike Slip fault: Transforms

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

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

More Related