Linking tectonics to impact and vulnerability

• A comlex set of factors determine the effects of a tectonic disaster, in the short and long term. It's not just the magnitude, it includes the location and characteristics of the population affected. Therefore, a strong link to risk, resilience and vulnerability.
• Richter scale

  • earthquakes
  • 0-9
  • magnitude scale
  • Measures the height (amplitude) of waves produced by an earthquake
  • Is an absolute scale, no matter where in the world the earthquake was, it would measure the same
• Mercalli scale

  • earthquakes
  • I-XII
  • intensity scale
  • Meaures the experienced impacts of an earthquake
  • It is a relative scale, because people experience different amounts of shaking in different places
  • it is based on a series of key responses, such as people awakening, the movement of furniture and damage to structures
• Moment Magnitude Scale (MMS)

  • earthquake
  • 0-9
  • A modern measure used by seismologists to describe earthquakes in terms of energy released
  • The magnitude is based on the ‘seismic moment’ of the earthquake, which is calculated from: the amount of slip on the fault, the area affected and an Earth-rigidity factor
• Volcanic explosivity index (VEI)

  • volcanic eruptions
  • 0-8
  • A relative measure of the explosiveness of a volcanic eruption, which is calculated from the volume of products (ejecta), height of the eruption cloud and qualitative observations
  • The VEI is logarithmic: an increase of one index indicates an eruption that is ten times as powerful
• Tectonic hazard profiles

  • A hazard profile compares the physical processes that all hazards share and helps decision makers identify and rank hazards that should be given the most attention and resources
  • A difficulty is the degree of reliability when comparing event types eg an earthquake to a tsunami/ volcanic eruption as they have different impacts on society and varying spatial distributions
• World risk index (DRI)

  • Assesses risk of disaster
  • calculated country by country through the multiplication of exposure and vulnerability