Paper 1 - Natural Hazards Flashcards
What is a natural hazard?
A natural event that threatens people and has the potential to cause damage, destruction and death.
E.g. Earthquake or Volcanic eruption
What are the factors affecting hazard risk?
Magnitude
Location
Time(of day)
Wealth
Education
Natural factors
Population density
What is a hazard risk?
The probability or chance that a natural hazard may take place. These factors can also cause hazards to impact communities differently.
What happens at a conservative plate margin?
Two plates are moving side by side each other.
They can move in different directions or the same direction at different speeds.
E.g. Pacific plate and North American plate
There can be violent earthquake activity but NO volcanic activity.
What happens at a Constructive plate margin?
Two plates move apart causing magma to rise to the surface.
Gentle volcanic and earthquake activity happen here and shield Volcanoes.
E.g. North American plate and Eurasian plate at the Mid-Atlantic Ridge.
What happens at a destructive collision plate margin?
Two plates move towards each other. Both plates are made of continental crust so neither subducts. Instead the two plates collide, crumbling the crust.
Earthquake activity and fold mountains but NO volcanoes.
E.g. Indo-Australian and Eurasian plates
What happens at a destructive subduction plate margin?
Two plates move towards each other. The dense oceanic plate is subducted underneath the less dense continental plate.
Violent volcanic and earthquake activity, composite volcanoes and fold mountains happen here.
E.g. Philippine plate subducts under the Eurasian plate.
The definition of Primary effects
The initial impact of a natural event on people and property, caused directly by it, for instance the ground buildings collapsing following an earthquake.
The definition of Secondary effects
The after effects that occur which are indirect impacts of a natural event, usually as a result of a primary effect,
Definition of immediate response
People’s reactions as the disaster happens and immediately after the hazard.
Definition of long term response
Later reactions that occur in the weeks, months and years after the event.
What are some Primary effects?
People are injured or killed
Buildings, properties and farmland is destroyed
What are some Secondary effects?
Tsunami
Shortages of drinking water, food and shelter
Spread of disease
Economic promblems
What are some immediate responses?
Evacuation
Emergency services
International aid
What are some long term responses?
Rebuilding settlements and infrastructure
