Earthquake

Back to: GEOGRAPHY SS3

 

Welcome to class! 

In today’s class, we will be talking about earthquake. Enjoy the class!

Earthquake

An earthquake is a sudden shaking of the earth’s surface, which may be violent enough to cause great damage. This is due to a sudden and rapid displacement of crustal rocks beneath the earth’s surface. It occurs as a result of disturbances or movement within and below the earth crusts.

Origin or Focus: This is the point where an earthquake originates i.e. the shock waves are set out from this point.

Epicentre: This is the point on the earth’s surface directly on top of the origin where the effect of the earthquake is greatest.

Seismograph: This is the instrument used to measure the intensity of the earthquake.

Richter scale: This is the scale that indicates the point of an earthquake or the magnitude of the shock.

Evaluation

1. Define an earthquake.
2. Explain the origin of an earthquake.

Effects of earthquake

1. They are disastrous and destructive to life and property.
2. They destroy roads, railways, bridges, power line and telecommunication lines.
3. They can cause and create large openings on lands.
4. They can raise and lower sea levels.
5. They also displace parts of the earth’s crust either vertically or laterally.
6. They can also raise or lower parts of the ocean floor.
7. They can cause landslides and open up deep cracks in surface rocks.

General evaluation

1. What are the causes of earthquakes?
2. Explain focus, epicentre and seismograph.
3. List four effects of an earthquake.
4. Differentiate between weather and climate.
5. State five elements of climate.

Reading assignment 

Essential Geography, Pages33-34.

Weekend assignment

1. The intensity of an earthquake is measured with (a) Seismograph(b) Ritcher’s scale (c) Campbell stoke (d) Barometer
2. The point an earthquake first appears directly above the surface is called(a) Epicentre (b) Focus (c) Origin (d) Core
3. The point at which the earthquake first began is called(a) Focus (b) Epicentre (c) Vent (d) Lithosphere
4. Earth tremor is simply the _______ of the earth crust (a) folding (b) shaking (c) weathering (d) formation
5. The magnitude of the earthquake is measured by ______ (a) Seismograph (b) Ritcher’s scale (c) Campbell stoke (d) Barometer

Theory

1. State two causes of earthquake.
2. Outline three effects of an earthquake.

 

In our next class, we will be talking about Volcanicity.  We hope you enjoyed the class.

Should you have any further question, feel free to ask in the comment section below and trust us to respond as soon as possible.

School Owner? Looking for ready-made content and tools to save time and grow easily? Book a free demo session now

Get more class notes, videos, homework help, exam practice on Android [DOWNLOAD]

Get more class notes, videos, homework help, exam practice on iPhone [DOWNLOAD]