Earthquake and volcanism

• Earthquake


  A sudden movement of the ground caused by too much stress building up in rocks that tend to rupture
• Seismograph


  An instrument to detect and record earthquake vibrations
• Seismologist


  A scientist that studies earthquakes
• Types of earthquakes

  • Tectonic earthquakes
  • Volcanic earthquakes
  • Collapsed earthquakes
  • Explosion earthquakes
• Tectonic earthquakes

  Force movement of tectonic plates
• Volcanic earthquakes


  Conjunction with volcanic activities
• Collapsed earthquakes


  Underground mines
• Explosion earthquakes


  Nuclear and chemical devices
• Anatomy of an earthquake

  • Focus/ hypocenter
  • Epicenter
  • Fault
  • Seismic waves
• Focus/ hypocenter


  A point where earthquake energy originates
• Epicenter


  Point directly above the focus
• Fault


  Runs along the edges
• Seismic waves

  Transmit energy by an earthquake
• Types of seismic waves

  • Body waves
  • Surface waves
• Body waves


  Travel through interior part of earth
• Primary waves/ p waves


  The 1st one to detect, fastest travel through solid and liquid
• Secondary waves/ s waves

  Larger than p waves, only move in solid
• Surface waves

  Travel through surface, cause damage to structure
• Love waves

  Fastest, move side to side
• Rayleigh waves


  Move horizontally and vertically, up and down forward and backward
• Magnitude


  Measure the energy of an earthquake in hypocenter
• Richter scale


  Created by Charles F. Richter to measure earthquake magnitude
• Intensity


  Describe the strength of shaking in a given locality
• Mercalli scale


  1 to 7 scale to measure the intensity of an earthquake's effects
• Intensity 7


  Total destruction of cities and changes to the earth's surface
• Volcanism


  Associated with volcanic activities with discharge of molten rock, pyroclastic fragments, hot water and steam
• Volcano


  A hill or a mountain that has a vent formed by lava
• Types of volcanism

  • Extrusive volcanism
  • Intrusive volcanism
• Extrusive volcanism


  Comes out on the earth's surface
• Intrusive volcanism


  Magma solidifies at the inner earth's crust
• Parts of a volcano

  • Crater
  • Vent
  • Conduit
  • Magma chamber
• Crater


  Funnel shape
• Vent


  The opening of the earth's surface
• Conduit


  A pipe-like passage where magma travels up
• Magma chamber

  A reservoir
• Volcanic materials

  • Pyroclastic materials/ tephra
  • Gases
  • Magma inside
  • Lava outside
• Pyroclastic materials/ tephra


  Materials that are emitted during volcanic eruptions
• Volcanic bombs


  Large fragments of rocks
• Lapili/ cinder


  Smaller pieces of rock
• Gases


  Dangerous to animals and humans