1. Ground Deformation: Faulting and Folding Earthquakes and Mountain- Building

2. Seismic Waves Seismology
The study of the propagation of mechanical energy: released by an
earthquake and explosions through the Earth is known as Seismic
waves
When energy is released in this fashion, waves of motion (like the
effect of a pebble tossed into a pond) are set up in the rocks
surrounding the source of the energy (the focus).
Seismic Waves
Waves are started because of initial tension or compression in the
rock which is known as stress.
Instruments used to measure these waves are called seismographs.

4. Key Earthquake Terms
Earthquake: The rapid vibration of the Earth’s surface
created by the sudden movement of rock bodies past each
other along a fault.
Fault: The place where there is movement on the Earth’s surface.
(faults come in all scales from mm to kilometers in length)
Focus: The site of initial rupture, this generally occurs below
the Earth’s surface.
Epicenter: The point on the Earth’s surface directly above
the Focus.

5. Energy released radiates in all directions from its source, the focus
Energy from an earthquake propagates in the form of seismic waves

8. L-wave

9. Seismographs are very sensitive instruments around the world that record the event(s) (Earthquakes)

10. Seismograph

12. What is a Fault or Fault line?

13. A Fault is a fracture in rock along which displacement has taken place- associated with a plate boundary. Faults can be active or inactive, and can be associated with either current or old plate boundaries.

17. Types of Faults

18. Normal

23. Reverse

26. Normal Faults
Reverse Faults

27. Strike-slip

34. What causes an Earthquake??

38. So, how does energy released by slippage at a fault travel through the ground?

39. Detecting and Locating Earthquakes

43. L-wave

44. Surface Waves

45. Energy from an Earthquake travels in seismic waves.

52. How far is the epicenter of an earthquake from a seismic station, if the difference between the arrival time of the P and the S wave is 5 minutes?

57. The P-Wave Shadow Zone
P-waves travel through the liquid outer core bend, leaving a low intensity shadow zone 103 to 143 degrees away from the source, here shown as the north pole
HOWEVER, P-waves traveling straight through the center continue, and because speeds in the solid inner core are faster, they arrive sooner than expected if the core was all liquid.
Behavior of waves through center reveal Earth’s Interior

58. The S-Wave Shadow Zone
Since Shear (S) waves cannot travel through liquids, the liquid outer core casts a larger shadow for S waves covering everything past 103 degrees away from the source.

59. Folding

66. Folding creates non-volcanic mountains

67. Folded Mountains

69. Fault-Block Mountains

75. Domed Mountains

77. Normal Faults
Reverse Faults