1. Geography of Earthquakes: Getting
Western Canada Ready For The Big One

2. What is an Earthquake?
• An earthquake is a sudden, sometimes violent,
shaking of the ground caused by the sudden
release of stored energy within the Earth’s crust
• Earthquakes are natural events, like snowstorms or
tornadoes
• Part of an ongoing geologic process that shapes
the surface of our planet

3. What is an Earthquake?
• Earth’s surface sits upon seven large, and several
smaller, crustal plates that are constantly in motion
over the planet’s molten core
• There is continuous force within and between each
of these plates
• When the rock can no longer withstand this stress
they suddenly break or slide creating an
earthquake

4. Seven major crustal plates
and several minor plates

5. 80% of all earthquakes occur
in the circum-Pacific belt

6. Seismic Activity
• The west coast of BC is the
most active seismic area in
Canada
• 300 small quakes occur
along the Juan de Fuca
subduction zone every year

7. Seismic Activity

8. How are quakes measured?
• The Richter scale measures the amount of energy
released at the hypocentre
• Each step on the scale is ten times greater than the
previous one

9. Earthquake Vocabulary
• Seismic: having to do with earthquakes
• Subduction zone: long region with a trench
through which a descending tectonic plate is
assimilated into the earth’s surface
• Epicenter: the Earth’s surface directly above the
quake
• Richter scale: a measure of the power of
earthquakes

10. Disaster Planning
• Working in groups of four, imagine how you would
respond to an earthquake here in Vancouver
• Outline the potential dangers and hazards in your
community
• Develop a list of the provisions and equipment you
would need in the event of an earthquake
• Make a poster with your group’s ideas, be creative