Ground shaking

• Ground shaking and displacement
  • EQ waves arrive in a distinct sequence
  • Different waves cause different motion
  • Affect much larger area than local faulting
• P waves are the first to arrive
  • Produce rapid, bucking,
  • up-and-down motion

• S waves arrive next
  • Produce a pronounced back-and-forth motion
  • Motion usually stronger than from P waves
  • S waves can cause extensive damage

• Surface waves slower – traveling on the surface
  • L waves follow quickly behind the S waves
  • Cause the ground to writhe laterally

• R waves are the last to arrive
  • Land surface undulates like ripples across a pond
  • Usually last longer than other wave types
  • R waves cause extensive damage

Pages: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23