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• Potential Earthquake Hazards


  • Ground shaking
  • Ground rupture/ground displacement
  • Liquefaction
  • Tsunami
  • Earthquake-induced landslide
  • Earthquake-induced ground subsidence
• Ground shaking


  Disruptive up, down and sideways vibration or movement of the ground during an earthquake
• Ground rupture/ground displacement


  Deformation on the ground that marks the intersection of the fault with the earth's surface
• Ground rupture


  • Length depends on the magnitude of an earthquake. Earthquake with 6.5 magnitudes and above will result to larger rupture
  • Width - deformation along the length of ground rupture also largely depend on the type of faulting
• Liquefaction


  Transformation of the behavior of a body of sediments or soil form to liquid form. It is a process caused by water pressure which makes soil more compact. It decreases the ground's ability to support structures
• Tsunami


  Series of waves caused by an earthquake under the sea. Wave's height could be greater than 5 meters. It is also known as tidal waves.
• Earthquake-induced landslide


  Down slope movements of rocks and other debris commonly triggered by strong shaking. It may include soil, debris, and/ or rocks.
• Earthquake-induced ground subsidence


  Sinking or settling of the ground surface due to various causes, such as extraction of ground water and natural gas, mining and earthquakes
• Earthquake has the following potential hazards: Ground shaking, ground rupture, tsunami, liquefaction and earthquake induced landslide and ground subsidence.
• Ground shaking is disruptive up, down and sideways vibration or movement of the ground during an earthquake.
• Ground Rupture/ Ground Displacement is a deformation on the ground that marks the intersection of the fault with the earth's surface.
• Liquefaction is losing of soil particles because of water pressure.
• Tsunami is series of waves caused commonly by an earthquake under the sea.
• Earthquake-induced landslide is a down slope movement of rocks and other debris commonly triggered by strong shaking. It may include soil, debris, and/ or rocks.
• Earthquake-induced ground subsidence is the sinking or settling of the ground surface.
• Hazard map


  A purposive material or tool which provides the necessary information and guide in procurement of peoples understanding, awareness and mitigation of the risks from natural hazards. It also consists of predicted risk areas, specified designed locations (facilities and shelters) for evacuation measures. Also, hazard maps must be easy to use and understand for immediate evacuation purposes by its users.
• Hazard maps can be accessible and maybe combined with the disaster management information of the locale (i.e. evacuation site, evacuation routes etc.)
• Map interpretation


  The process looking at the map in order for us to be guided to a direction or place where we wanted to go using the different symbols or elements of the map.
• Important components of a map

  • Compass rose
  • Title
  • Symbols
  • Legend or Key
  • Color
  • Scale
  • Grid Reference
• Seismic Design Category (SDC)


  An indicator of how much attention must be paid to the seismic design and construction of a building. It ranges from "A" to "E". Buildings with an SDC of "A" must be designed for seismic forces, but do not require any special seismic attention. Buildings with an SDC of "E" require a tremendous amount of seismic care and attention.
• Seismic Design Categories and associated earthquake hazard potential

  • SDC A - Very small probability of experiencing damaging earthquake effects
  • SDC B - Could experience shaking of moderate intensity
  • SDC C - Could experience strong shaking
  • SDC D0 - Could experience very strong shaking (the darker the color the stronger the shaking)
  • SDC D1 - Could experience very strong shaking (the darker the color the stronger the shaking)
  • SDC D2 - Could experience very strong shaking (the darker the color the stronger the shaking)
  • SDC E - Near major active faults capable of producing the most intense shaking
• Why are Hazard Maps Important? Hazard maps are very important because it provides us information to help not only our family members but also other people understand the risks of natural hazards and to help mitigate disasters. Hazard maps indicate the extent of expected risk areas at home and community and can be combined with disaster management information such as evacuation sites, evacuation routes, and so forth