Plate Tectonics Theory

1. Plate Tectonics
Theory

2. Plate Tectonics
Theory
Plate tectonics is a scientific theory that explains how major
landforms are created as a result of Earth’s subterranean
movements. The theory, which solidified in the 1960s,
transformed the earth sciences by explaining many phenomena,
including mountain building events, volcanoes, and earthquakes.

3. In plate tectonics, Earth’s outermost
layer, or lithosphere—made up of the
crust and upper mantle—is broken into
large rocky plates

4. • Due to the convection of the asthenosphere
and lithosphere, the plates move relative to
each other at different rates, from 2 to 15
centimeters (one to six inches) per year.

5. Himalayas mountain range in Asia East African Rift
San Andreas Fault in California, United States.

6. Alfred Wegener published two articles about a concept called
continental drift in 1912.

7. What is Continental Drift
•
•

8. •
Pangaea

9. •
Pangaea
•

10. Plate Boundaries
A plate boundary is a three-dimensional surface or zone across
which there is a significant change in the velocity (speed or
direction) of motion of one lithospheric plate relative to the
adjacent lithospheric plate.

11. In some ways, Earth resembles a giant jigsaw puzzle. That is
because its outer surface is composed of about 20 tectonic plates,
enormous sections of Earth’s crust that roughly fit together and
meet at places called plate boundaries.

13. There are 3 types of Plate Boundaries
Convergent boundary
Divergent boundary
Transform boundary

14. Divergent boundary
A divergent boundary or divergent plate
boundary is a linear feature that exists between
two tectonic plates that are moving away from
each other.

15. Divergent boundary
A divergent boundary or divergent plate
boundary is a linear feature that exists between
two tectonic plates that are moving away from
each other.

16. Divergent boundary
Divergent boundaries within continents
initially produce rifts, which eventually
become rift valleys.
Iceland stretches
Mid-Atlantic Ridge

17. Convergent boundary
Convergent boundary is an area on earth where
two or more lithospheric plates collide.

18. Convergent boundary
Convergent boundary is an area on earth where
two or more lithospheric plates collide.

19. Convergent boundary
One plate eventually slides
beneath the other, a process
known as subduction.
Himalayas mountain
Convergent boundary is an area on earth where
two or more lithospheric plates collide.

20. Transform boundary
A transform fault or transform boundary,
sometimes called strike-slip boundary, is a fault
along a plate boundary where the motion is
predominantly horizontal.
San Andreas Fault

21. Trivia Time!

22. Following World War II, even more evidence was uncovered which supports the
theory of plate tectonics. In the 1960's a world-wide array of seismometers
were installed to monitor nuclear testing, and these instruments revealed a
startling geological phenomenon. It showed that earthquakes, volcanoes, and
other active geologic features for the most part aligned along distinct belts
around the world, and those belts defined the edges of tectonic plates.
Did you know?

23. AstroPraym

24. Thank you!