Friday 9 September 2011

Why is the earth's crust unstable?



Section
Detail
Key Ideas
  1. The earth's crust is unstable, especially at plate boundaries.
  2. There are differences between oceanic and continental plates.
Terms
crust, plate, plate boundary/margin, mantle, convection currents
Starter
Apple. NT p8 A
Main
1.   TDIT.
2.   Students draw cross-section of earth and annotate with Key Terms.
3.   Pack of cards/plates simile.
4.   Students examine examples of basalt and granite for differences between oceanic and continental crust (physical and/or videos below).
5.   Students draw diagram NT p9 B
6.   NT p9 Qus 2b
Plenary
a.   What are the two types of plate called?
b.   Give one difference between them.
c.   What is the name for where plates meet?
d.   What causes the plates to move?
Granite
Basalt