Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Ever Changing Earth
Transcript of Ever Changing Earth
It all started with people looking at maps and making observations.
looked at maps
and developed the theory of
the theory states that the continents were once joined together in a single landmass called
unfortunately, Wegener could not explain why the continents were moving.
. . . discovered that the continents were moving away from each other at the mid ocean ridges.
This is called
The combination of Wegener's Theory of Continental Drift and Hess's evidence of Sea Floor Spreading led to the development of the Theory of Plate Tectonics . . .
. . . the theory that the earth's surface is divided into giant plates that are in constant motion
The movement of the plates is caused by the circular motion of the hot rock in the mantle of the earth.
This movement is called
Convection currents are responsible for . . .
The Layers of the Earth are . . .
We know about the inside of the Earth because of observations of Seismic Waves and also from analysis of rocks from drilling.
By the way, did you know the difference between Magma and Lava?
Magma = molten rock and gasses in the Mantle
molten rock on the surface
Now, let's see what's going on under the Earth's surface.
As you can see, the Earth is in a constant state of change. It is never the same from minute to minute!
the three plate boundaries are
divergent - the plates move away from each other
convergent - the plates move toward each other
transform - the plates slide next to each other
The energy from an earthquake travels in waves.
Earthquake energy is measured using the Richter scale.
Earthquake damage is measured with the Mercalli scale.
The location beneath the surface of the earth where the rocks break is called the focus.
The location on the surface of the earth above the focus is called the epicenter.
Using data from three earthquake monitoring stations we can locate the epicenter using a process called triangulation.