Chapter 7 Chapter 4 in Old Textbook

1
Chapter 7Chapter 4 in Old Textbook pg. 115

• Plate Tectonics
• How did it happen?

2
Chap 7, Sec 1A (Convection Currents and the
Mantle)

• Objectives
• How is heat transferred?
• What causes convection currents?
• Sea-Floor Spreading

3
(No Transcript)
4

• Tech Terms
• heat transfer when energy moves from a warmer
  object to a cooler object (water in ice cube tray
  transfers heat to inside of freezer).
• When you open the front door in the winter are
  you letting the cold air in, or the warm air out??

5

• radiation heat transfer that requires NO direct
  contact between a heat source and an object.
• conduction heat transfer by direct contact of
  molecules of matter.

6
(No Transcript)
7

1. convection heat transfer by movement of fluid
   (liquid or gas).

Red/Blue Dye Demo
8
(No Transcript)
9
(No Transcript)
10

• convection current created when there are
  differences in temperatures and densities within
  fluids (liquid or gas).
• The heating and cooling of the mantle material
• (which changes its density) and the force of
  gravity are what powers the convection currents.

11
(No Transcript)
12
One More Time!
13
So Whats Next?

• How does this movement create continental drift?
• How is Sea Floor Spreading Related?

14
Sea Floor-Spreading

• 6. mid-ocean ridge longest chain of mountains
  extending into all of Earths oceans, that curves
  like the seam of a baseball along the sea floor.

15
(No Transcript)
16

• sea floor spreading the process that adds new
  material to the ocean floor at the mid-ocean
  ridge. Molten material erupts and spreads out
  through the valley that runs along the center of
  the mid-ocean ridge.
• It then pushes aside the rock that was already
  there.

17

• Its all about
• CONVECTION CURRENTS!!!!!!