Earthquake 1

• Fault


  A break or fracture in the crust of Earth
• Earthquake


  Shaking or trembling of the earth caused by movement along a fault
• Types of faults


  • Strike-slip fault
  • Normal fault
  • Reverse fault
• Normal fault


  • The block above the fault has moved downward relative to the block below
• Reverse fault


  • The block above the fault moves up relative to the block below the fault
• Strike-slip faults


  • Vertical (or nearly vertical) fractures where the blocks have mostly moved horizontally
• Dextral fault


  A strike-slip fault where the blocks have moved horizontally in a right-handed sense
• Sinistral fault


  A strike-slip fault where the blocks have moved horizontally in a left-handed sense
• Geological folding


  1. Plastic deformation (bending, buckling) of a single or multiple (stack) strata

  2. Structural failure and faulting
• Folds


  • Classified according to size, fold shape, tightness, and dip of the axial plane
• Pressure on rocks


  Can deform or break them, causing folds or faults
• Anticlines


  • Folds that go up
• Synclines


  • Folds that go down
• Fault line


  Water can flow through the crack and form beautiful cave formations
• Earthquakes


  • Occur when rock shifts or slips along fault lines
• Earthquakes


  1. Generate waves that travel through the earth's surface

  2. These waves cause damage around the epicenter
• Ground shaking


  Consequence of movement of seismic waves through the ground
• Seismic waves


  Caused by the sudden movement of materials within the Earth, such as slip along a fault during an earthquake
• 1. waves


  • Primary body waves; first seismic wave detected; able to move through both liquid and solid rock
• 1. waves


  • Secondary body waves that oscillate the ground perpendicular to the direction of wave travel; travel about 1.7 times slower than P waves; will not travel through liquids
• Love waves


  • Only form on the surface of the Earth after a large earthquake; have a horizontal back and forth motion
• Rayleigh waves


  • Move the surface of the earth around in a circle, forward and down then back and up