2. http://www.youtube.com/
watch?v=Kpoko_l34ZE&fea
ture=related
http://www.youtube.com/
watch?v=ryrXAGY1dmE&fe
ature=related

3.  The lithosphere is broken into separate sections
called plates. They “float” on the asthenosphere
 Sea-floor spreading and continental drift into a
single theory – The Theory of Plate Tectonics
 Plate Tectonics – is the geological theory that states
that pieces of Earth’s lithosphere are in
constant, slow motion, driven by convection currents
in the mantle.
 The theory of plate tectonics explains the
formation, movement, and subduction of Earth’s
plates

5. 1. Transform Boundaries –
 Crust is neither created nor destroyed
 Place where two plates slip past each
other, moving in opposite directions

6. 2. Divergent Boundaries
 Place where two plates move apart
 When develops on land, two of Earth’s plates
pull apart. A deep valley called a rift valley
forms along the divergent boundary

7. 3. Convergent Boundaries
 Place where two plates come together
 Converging oceanic plate and oceanic plate collide one
plate is subducted through a trench and volcano islands
are formed
 Converging oceanic plate and continental plates – when
continental plates and oceanic plate collide, the oceanic
plate is subducted and volcanoes on land are formed
 Converging continental plates – where two continental
plates collide, the crust buckles and mountain ranges
form.

8.  The plates are moving at a very slow rate of about one
to ten centimeters per year.
 In areas plates are moving together and others are
moving apart.