Notes
seismic hazards
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Seismic Hazards
Nature and Distribution
Slow build-up of stress in crust
Pressure released
Causes ground to shake
Focus – in crust
Epicentre – point on earth’s surface
Depth
Deep focus – 300700 km
Intermediate focus – 70300 km
Shallow focus – 070 km – most damaging
Conservative boundary
Distribution
Occur at plate boundaries
Conservative
Anomalies
Intraplate deformation
Human activity
Magnitude
Richter scale
110
Logarithmic
Mercalli scale
112
Intensity and impact
Based on human observations
Frequency
Seismic records
Seismometer – detects shaking of ground
Historical records
Effects of seismic events
Primary impacts
Immediate
Ground rupture
Ground shakings
Secondary impacts
Landslides/avalanches
In glaciated areas
Tsunami
Fires
Building collapse
Soil liquefaction
Tsunamis
Giant sea wave
Shallow focus (underwater EQ)
Long wavelength (100km+)
Travel up to 700km/h
As they reach land rapidly increase in height (over 25m tall)
Effects
Disease
Depend on
Waring systems
Coastal geography
Population density
Distance travelled
Infrastructure destroyed
People injured by debris
Frowning
Wash coastal structures inland
Managing seismic hazards
Prediction
Frequency
Random
Radon gas
Animals
Magnetic fields
Plate boundaries
Prevention
Impossible
Protection
Insurance
Aid
Land-use planning
Tsunami protection
Hazard resistant structures
Education
Fire prevention
Emergency services
Information
- Description
- A level Geography (Hazards) Note on seismic hazards, created by Orlagh Bonser on 05/04/2018.
- Created by
- Orlagh Bonser
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