Where two plates move
towards each other. The
denser plate subducts
beneath the other,
friction causes it to melt
and become molten
magma. Also responsible
for earthquakes.
Constructive
When two plates are
moving away from
each other, magma
rises from the mantle
to fill the gap and
cools creating new
crust.
Conservative
Where two plates are
moving sideways past
each other or are
moving in the same
direction but at
different speeds. Crust
isn't created or
destroyed.
Earthquakes
Caused when two plates collide.
Tensions build up when one plate
gets stuck as it's moving
down past the other in the
mantle. Can occur at all plate
margins.
LIC: Haiti
Earthquake - 2010
Magnitude -
8.8
Effects
500 killed, 12,00 injured
500,000 homes
destroyed
Santiago's
airport was slightly
damaged.
Several Pacific
countries were
hit by the
tsunami.
Responses
A national
telethon
raised
$60million.
After an earthquake in
1960, all new buildings
were built to withstand
earthquakes.
HIC: Chile Earthquake -
2010
Effects
1.3million made
homeless 8
hospitals destroyed
2million left with
no food/water,
serious looting.
Many dead bodies
in hot
temperatures
became a health
hazard.
Magnitude - 7.0
Responses
Route 5 was fixed
24 hours later
After one year, there
were still 1,300
camps for the
homeless.
Volcanoes
Destructive
plate margin
Oceanic plate goes under
the continental plate.
Oceanic plate moves into
the mantle, melted and
destroyed. Magma forms
then rises through cracks
in the crust. Magma (Lava)
erupts onto surface.
Constructive
plate margin
Magma rises up into
the gap created by the
plates moving apart.
When a volcano erupts, it
emits lava and gases. Some
emit ash, block out the sun
and form pyroclastic flows.
Living with
Tectonic
Hazards
Why people live in
areas at risk?
Don't want to
leave their
families/friends
Soil around volcanoes is
fertile because of the
minerals from the ash and
lava.
Employed
in the area
Management
Reduces the
Effects
Montoring
Seismometers
monitor earth
movements, and can
be used in early
warning systems.
Prediction
By monitoring the
movement of tectonic
plates. Gives people time
if they need to evacuate
- less deaths/injuries
Protection
Buildings designed to
withstand earthquakes
Automatic shut-off
switches are fitted
to turn off
electricity supplies
to prevent fires.
Buildings can be
strengthened so they're
less likely to collapse.
Planning
Emergency services can train
and prepare for disasters
Governments can plan
evacuation routes to get
people out of dangerous
areas quickly and safely.
People can be educated so
that they know what to do
if a disaster happens.
Natural
Hazard
A natural hazard is a
natural process which
could cause death,
injury or disruption to
humans.
Geological
Hazard
Caused by land and
tectonic processes e.g
volcanoes and
earthquakes.
Meteorological
Hazard
Caused by weather and
climate e.g tropical storms.