The document discusses two scales used to measure earthquakes: 1) The Richter scale is a scale from 0 to 10 that measures the power of an earthquake based on scientific recordings, with each increase of 1 representing a 10 times increase in power. 2) The Mercalli scale describes and compares the effects of an earthquake on a scale of I to XII by evaluating the damage done at a location. 3) Earthquakes are measured using scientific instruments like seismographs, which detect and record the movement of the ground to measure the strength and effects of an earthquake.

1. Logarithmic scale. That means an
eruption 10 times bigger than the
one below.
So, a magnitude 6 earthquake is
10 times more powerful than a
magnitude 5, and 100 times more
powerful than one measuring 4.
Richter scale
 a scale ranging from 0 to 10 used for
measuring earthquakes, based on scientific
recordings of the amount of movement.
Measured using a seismograph.
Mercalli scale
 a means of measuring earthquakes by
describing and comparing the damage done on a
scale of I to XII
Key Vocabulary
Science Guy
-
Earthquakes
GCSE
Bitesize
How are earthquakes measured?
LO: To understand the distribution of earthquake hazards and the effects and responses to an earthquake.

2. Mercalli Scale
How are earthquakes measured?
LO: To understand the distribution of earthquake hazards and the effects and responses to an earthquake.

3. Tectonic activity can only be measured by
instruments. There is no visible effect on the
land or people.
Sounds like a rumble of traffic. People
sitting down can feel it and electric wires
outside may sway.
People begin to be afraid. If they are sleeping
then they will wake up. Hanging objects
indoors sway and unstable objects may fall.
Some drivers may even notice the shock.
Most people take protective action and are
very afraid. Heavy furniture may move or
even fall over. Windowpanes will smash and
driving will be very difficult.
People find it difficult to stand. Houses
are damaged as wall tiles fall off and
windows smash. Underground pipes
burst.
People are tossed around by the quake.
Furniture will fly around rooms. Buildings
will crack and roads may begin to split
open.
Houses collapse trapping people inside.
Bridges are destroyed and large cracks
begin to appear in the ground.
Total destruction! The ground rises and
falls.
1 2 3 4
5 6 7 8
Illustrate the different impacts caused by
earthquakes of varying magnitudes on the Richter
Scale.
How are earthquakes measured?
LO: To understand the distribution of earthquake hazards and the effects and responses to an earthquake.
Using the Richter
Scale sheet,
illustrate each stage
of the scale with a
picture that
represents the
correct strength of
earthquake. Use the
box descriptions to
help you.

4. LO: To explain the distribution and features of earthquakes and know how they are measured.
Draw a quick diagram of the
Seismograph in your books, then in
your own words explain how the
machine would record the
earthquake to produce an
earthquake trace.
Trace

5. How are earthquakes measured?
LO: To understand the distribution of earthquake hazards and the effects and responses to an earthquake.
Using the handout
sheet from your
teacher. Complete
the sheet that
shows the
earthquake trace for
the 2011 Japanese
Tsunami.