Theory of Plate Tectonics “The Earth is like a cracked eggshell!”

Lithosphere  The lithosphere is broken into separate sections called plates.  The plates carry the continents, the ocean floor or both.

Theory of Plate Tectonics  Plate Tectonics is the geological theory that states that pieces of Earth’s lithosphere are in constant motion, driven by convection currents in the mantle.  The theory of plate tectonics explains the formation, movement, and subduction of Earth’s plates

Plate Movement  No plate can budge without affecting the other plates surrounding it.  As plates move, the changes include volcanoes, mountain ranges, deep-sea trenches, and earthquakes.

Plate Boundaries  Transform Boundaries  Along a transform boundary, crust is neither created nor destroyed.  A place where two plates slip past each other, moving in opposite directions.

Plate Boundaries  Divergent Boundaries  The place where two plates move apart is called a divergent boundary.  Most divergent boundaries occur at the mid-ocean ridge.  On land, a divergent boundary is called a rift valley.

Plate Boundaries  Convergent Boundaries  The place where two plates come together, or converge.  When two plates collide, the density of the plates determines which one comes out on top.

The Moving Plates  The plates are still moving at a rate of about 1-10 centimeters per year!

Name the Plates