Plate Tectonic - Plate Tectonics (6)
Pre Lab 

  • Comparing plate boundaries.
  • Locating different plates.
  • converging
  • diverging
  • plate boundary
  • transform motion
  • worksheet
  • relief map of the world

Students name the plates on a world map.



According to the theory of plate tectonics, the Earth's crust and upper mantle are broken into moving plates of "lithosphere." The Earth has two types of crust. Continental crust underlies much of the Earth’s land surface. The ocean floors are underlain by oceanic crust. These materials have different compositions. Continental crust is less dense than oceanic crust.

All of the plates are moving. They are slow, moving at speeds of centimeters to tens of centimeters per year. They slide along on top of an underlying mantle layer called the asthenosphere, which is composed of a less rigid, almost viscous rock.

The plates are layers of rigid, solid rock. As they move, plates interact at their edges or boundaries. There are three basic directions or types of boundary interactions. In some places, two plates move apart from each other; this is called a diverging plate boundary. Elsewhere two plate move together called a converging plate boundary. Finally, plates can also slide past each other horizontally. This is called a transform plate boundary.

Volcanoes and earthquakes help define the boundaries between the plates. Volcanoes form mostly at converging and diverging plate boundaries, where much magma is generated. Earthquakes occur at all three types of boundaries. Because the plates are rigid, they tend to stick together, even though they are constantly moving. When the strength of the rocks at the plate boundary is exceeded, they move rapidly, "catching up" with the rest of the plates. We feel this release of energy as an earthquake.


This exercise focuses on allowing the students to put the information that they have learned in previous years into perspective.

  1. Show the students a world map with either plate boundaries or plots of Earthquakes and Volcanoes. The U.S. Geological Survey publishes a map called the "Dynamic Earth," that would be very useful. Point out the different plate boundaries to the class. These boundaries are not sharp lines but zones where the movement takes place. The lines on the map are just approximations. A relief map of the Earth, shows that mountain ranges seem to following the earthquake and volcano pattern.

  2. Review the three ways plates move with the class. Draw pictures on the board like the ones at the top of the second image below, or use the image itself.

  3. The plates were defined and named by geologists. Most of these scientists agree that there are 13 large plates, and many smaller ones. The exact total is not agreed upon. During lab, students will look at the data and decide for themselves if there are 13 plates or not. Using the worksheet, have the students make up names for the individual plates shown on the map. As a class, compare the students’ names with the real names of the plates, which are listed below.

1. Philippine Sea Plate
2. Indian - Australian Plate
3. Pacific Plate
4. Caroline Plate
5. Caribbean Plate
6. Cocos Plate
7. Nazca Plate
8. Antarctic Plate
9. Scotia Plate
10. Eurasian Plate
11. Arabian Plate
12. African Plate
13. South American Plate

  1. Students are also asked to look at features that might give them clues to plate boundaries. If they look at a generalized map, they will notice that mountain ranges are common to plate boundaries. In other areas volcanoes are common. If you live in a mountainous area and have a detailed local map, your students may notice that parallel mountains and valleys are common. These tend to form at converging plate boundaries in areas of compression.  

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