By the end of this lesson, you should be able to:
π§ Cognitive: Identify different earthquake-induced hazards.
π Affective: Demonstrate awareness of earthquake safety and preparedness.
β Psychomotor: Point out earthquake-prone areas using hazard maps or models.
An earthquake hazard is any dangerous event or condition caused by earthquakes that can harm people, property, livelihood, or the environment.
π Earthquake hazards may happen:
during shaking
right after shaking
minutes to hours later (like tsunami or landslides)
What it is:
The vibration or movement of the ground during an earthquake.
Why itβs dangerous:
causes buildings to sway or collapse
can throw people off balance
damages bridges, roads, and utilities
Areas most prone:
everywhere near the fault
soft ground shakes stronger than hard rock
Typical effects:
collapsed buildings, falling objects, injuries, broken lines.
What it is:
A visible crack or break on Earthβs surface when a fault moves.
Why itβs dangerous:
splits roads and buildings in half
destroys foundations instantly
permanent ground displacement
Areas most prone:
directly on or near a fault line
Typical effects:
offset pavements, torn pipelines, collapsed structures along faults.
What it is:
When water-saturated soil becomes soft like liquid during shaking.
Why itβs dangerous:
buildings sink or tilt
roads buckle
ground loses strength
Areas most prone:
coastal areas
river plains
reclaimed land
places with loose sandy soil + high groundwater
Typical effects:
tilted buildings, cracked ground, sand boils.
What it is:
Shaking causes rocks and soil to slide downhill.
Why itβs dangerous:
buries houses or roads
blocks rivers leading to flash floods
isolates communities
Areas most prone:
steep slopes
deforested mountains
areas with loose soil
Typical effects:
collapsed hillsides, blocked highways, buried homes.
What it is:
A sudden lowering or sinking of the ground after shaking.
Why itβs dangerous:
damages buildings and roads
increases flooding risk in lowlands
creates uneven ground
Areas most prone:
soft clay-rich soils
coastal plains
areas with over-extracted groundwater
Typical effects:
sunken roads, cracked foundations, water pooling.
What it is:
A ground movement where soil shifts sideways during shaking (often near bodies of water).
Why itβs dangerous:
drags roads and buildings sideways
breaks bridges, pipelines
happens fast and unpredictably
Areas most prone:
riverbanks
coastal areas
loose sandy soils
Typical effects:
sideways cracks, tilted posts, shifted houses.
What it is:
A series of large ocean waves caused by underwater earthquakes.
Why itβs dangerous:
floods coastal communities quickly
sweeps away houses, people, vehicles
may arrive minutes after shaking
Areas most prone:
coastal areas near trenches/faults
low-lying shorelines
Warning signs:
strong earthquake near coast
sudden sea level retreat
loud roaring sound
Typical effects:
coastal flooding, drowning, massive debris damage.
near active fault lines
coastal zones (tsunami + liquefaction)
river plains & reclaimed land
mountainous slopes (landslides)
old or poorly built buildings
houses with weak columns
unreinforced masonry
bridges and elevated roads
buildings constructed on soft ground
secure heavy shelves and appliances
identify safe spots (under sturdy table, near inner wall)
prepare a Go Bag
know evacuation routes
family emergency plan + drill
Duck, Cover, Hold
stay away from windows and falling objects
do not run outside while shaking
if outdoors, go to open area
if near coast, prepare to evacuate after shaking stops
check injuries first
inspect for gas leaks / fire hazards
evacuate damaged buildings
expect aftershocks
listen to official advisories