Factors influencing vulnerability to hazard
Rock Type
Permeable vs impermeable rock.
Building homes on permeable rock reduces the risk of liquefaction. This reduces the amount of water in the soil and so there is a lower risk.
Hard vs soft rock
If the rock is soft, when an earthquake occurs, there will be a greater risk of amplification and such greater risk of building collapse
Population Density
Higher density = more people at risk
Higher population density often means more people living in taller buildings which are at greater risk of collapse.
Frequency - how often a hazard event occurs
Low Frequency (1 in every 100 years or so)
Medium Frequency (1 in every 25 to 50 years)
High Frequency (1 in every 10 years or so)
Often countries are recovering from the last event and so have little time to prepare for the next one. E.g. Haiti
'Perpetual cycle of recovery'
Little preparation and often no one with 'lived experience' of the hazard. Government does little to reduce risk as this may be politically unpopular
People have knowledge of the hazard, government take steps to reduce risk e.g. volcano monitoring. Generally lower level of vulnerability than other scenarios.
Location
Proximity to plate margins is key. Closer, generally means higher risk. Most active faults around Pacific ring of fire.
Economic Development
Buildings
Monitoring
Education Programmes
Response
Building infrastructure which is a-seismically designed is expensive. These, hopefully, do not collapse during an EQ event.
With higher wealth, volcanoes can be monitored e.g. Mt Etna. This allows for prediction and evacuation. More monitoring = better forecasts and removes problem of evacuation fatigue.
TV adverts, social media and work in schools to tell people about hazards and what to do. This reduces the risk but is expensive.
Wealthy countries have more resources within the country e.g. search and resucue and so this means response is faster such lessening the secondary impacts
Relief
Rock Type
Permeable vs Impermeable
Shape of the land
Height above sea level
If there is a bowl shaped depression, when an earthquake occurs inside this bowl, the ground shaking will be amplified. This occured in the Nepal Earthquake of 2015.
If the rock is soft, this will increase the ground shaking and will lead to amplification.
Permeable rock will reduce the amount of moisture held in the soil. This reduces the risk of liquefaction and such the risk of building collapse.
If the location is well above sea level, the risk from Tsunmai waves is reduced.
Some locations do not have active volcanoes or earthquake faults and so the risk is zero (or close to! e.g. UK)