2. Introduction This power point presentation will explain how the surface of the Earth is always moving and always changing. Very large sections of the Earth’s crust called tectonic plates are constantly shifting and moving against one another. We will look at: The past and future movements of the tectonic plates the different ways the plates move against each other
3. Tectonic Plates Tectonic Plates are large shifting slabs of rock that make up the Earth’s crust. Most continents rest on their own tectonic plate. Since the plates are moving about as fast as your finger nail grows, the continents are also changing there position in relation to each other at that rate.
4. The Supercontinent 225 million years ago there was one supercontinent that geologists call Pangea Pangea was made of 7 large floating plates. Over time, these plates shifted to form the continental structure we have today. 250 million years from now, geologists believe that the continents will again form a supercontinent, which they are referring to as Pangea Ultima.
5. Pangea This is Pangea the large supercontinent from 225 million years ago when all continental plates were all connected together. (Reference)
6. Earth Today This is Earth in present day with all the plate boundaries. Tectonic plates move approximately as quickly as fingernails grow which is why it has taken the plates 225 millions years to get where they are. (Reference)
7. Pangea Ultima This is the supercontinent Pangea Ultima, where all the plates have shifted back together. This is what Earth is supposed to look like 250 millions years from now. (Reference)
8. The Plate Boundaries As the tectonic plates shift they move against one another at their plate edges; where plate edges meet are called plate boundaries. Three different plate movements occur at the plate boundaries, creating three different kinds of boundaries Divergent boundaries Convergent boundaries Transform boundaries
9. Divergent Boundaries A divergent plate boundary is where two plates are moving apart and magma pushes up into the crack. It then cools to form new crust.
10. Convergent Boundary A Convergent Plate Boundary is when two plates collide into one another. One of the plates will subduct under the other. Subduct means to slide underneath. There are three different types of convergent plate boundaries Ocean to Ocean Ocean to Continent Continent to Continent
11. Ocean to Ocean Ocean to Ocean Convergent Plate Boundary is when two ocean crusts collide. When this happens the older oceanic crust will be subducting under the younger crust.
12. Ocean to Continent Ocean to Continent Convergent Plate Boundary is when an oceanic plate collides with a continental plate. When this happens the oceanic plate subducts under the continental plate and causes coastal mountains or volcanoes.
13. Continent to Continent Continent to Continent Convergent Plate Boundary is when two continental plates collide. When this happens the two crusts can’t subduct so the collide and build large mountain ranges. An example of this would be the Himalayan Mountains in India.
14. Transform Boundary A Transform Plate Boundary is when two plates slide past each other. This kind of plate is the main cause of earthquakes. The best example of this is on the San Andreas Fault in California.
15. Conclusion In this lesson we learned that The Earth’s surface is made of many tectonic plates that move against each other. 225 million years ago all the plates were connected in one large landmass called Pangea. The plates shifted into the continents we have today The plates will continue to move into another large landmass called Pangea Ultima.
16. Conclusion In this lesson we also learned that As the plates move they either separate from (divergent boundary), collide with(convergent boundary), or slide past(transform boundary) each other.
17. Review Questions What is a Tectonic Plate? What is Pangea? What is Pangea Ultima? What are the three types of Plate boundaries? What kind of boundary is the San Andreas Fault? How did the Himalayan Mountains form?
