GEO: Our Changing Earth Flashcards
(44 cards)
What is the purpose of the paper pellet activity in the beaker?
To observe the movement of warm and cooler layers of water
This simulates the movement of molten magma inside the Earth.
What are lithospheric plates?
Large and small, rigid, irregularly-shaped plates that carry continents and the ocean floor
The lithosphere consists of these plates which move slowly due to magma movement.
How fast do lithospheric plates move?
Just a few millimeters each year
This slow movement is driven by the movement of molten magma inside the Earth.
What are the two types of forces that cause earth movements?
Endogenic forces and Exogenic forces
Endogenic forces act in the interior, while exogenic forces work on the surface.
What are examples of endogenic forces?
- Earthquakes
- Volcanoes
- Landslides
- Diastrophic forces
These forces can cause both sudden and slow movements.
What can sudden movements caused by endogenic forces lead to?
Mass destruction over the surface of the Earth
Earthquakes and volcanoes are examples of sudden movements.
What are examples of exogenic forces?
- Erosional forces
- Depositional forces
- River
- Wind
- Sea-waves
- Glaciers
These forces act on the surface of the Earth and shape landforms.
Fill in the blank: The movement of molten magma inside the Earth moves in a _______ manner.
[circular]
This circular movement is similar to the observed movement of the paper pellet in water.
True or False: Lithospheric plates are immovable.
False
These plates move slowly due to the underlying molten magma.
What is the result of the movement of lithospheric plates?
Changes on the surface of the Earth
This includes the formation of mountains and other landforms.
What is a volcano?
A vent (opening) in the earth’s crust through which molten material erupts suddenly
A volcano can also release gases and ash.
What are the vibrations called that occur when lithospheric plates move?
Earthquakes
These vibrations can travel all around the earth.
What is the focus in terms of an earthquake?
The place in the crust where the movement starts
It is the origin of the seismic energy.
What is the epicentre of an earthquake?
The place on the surface above the focus
Greatest damage usually occurs closest to the epicentre.
How do seismic waves behave in relation to the epicentre?
They radiate outwards from the epicentre as waves
The strength of the earthquake decreases away from the epicentre.
What are the three types of earthquake waves?
- P-waves or longitudinal waves
- S-waves or transverse waves
- L-waves or surface waves
Each type of wave has different properties and behaviors.
Complete the sentence: The greatest damage from an earthquake is usually closest to the _______.
epicentre
What happens to the lid of a boiling container filled with water, as described in the text?
The lid begins to shake and the items on top vibrate
This analogy illustrates how the earth vibrates during an earthquake.
What is the term used for the seismic waves that travel out in all directions?
Seismic waves
These waves are generated during an earthquake.
What are the two categories of processes affecting the earth’s crust as mentioned in the text?
- Endogenic
- Exogenic
These terms refer to internal and external processes affecting the earth.
What is used to measure an earthquake?
Seismograph
A seismograph records the intensity and duration of seismic waves.
On which scale is the magnitude of an earthquake measured?
Richter scale
The Richter scale quantifies the size of earthquakes.
What magnitude of an earthquake can be felt only a little?
2.0 or less
Earthquakes of this magnitude generally do not cause damage.
What magnitude is classified as a major earthquake?
7.0 or higher
Major earthquakes can cause significant damage and loss of life.
