Name: _______________________________________________ Date: ___________________ Block: _______
Unit 1 Notes – Plate Tectonics
I. The Changing Marine Environment
A. Did the oceans (white area) always look like this?
1. Since their formation, oceans have experienced considerable _________________________.
B. Alfred Wegener
1. Studied the close fit between the coastlines of ___________________ and _____________
_______________________________.
2. In ___________ , Alfred Wegener proposed The ____________________________
_____________________ Theory to explain the “jigsaw-puzzle” fit of some continents.
3. This theory proposes that landmasses at one point were part of a super-continent called
_______________________________.
4. The main piece of evidence used was how the continents appeared to
_____________________________________________________________________________.
C. _______________________________
1. Was a _____________________________ of Alfred Wegener’s theory.
2. Added to the theory that the supercontinent broke into ___________ mega-continents.
a. _____________________________ in the North
b. _____________________________ in the South
D. Current _____________________________________ in support of Alfred Wegener’s theory
1. ____________________________________________________________________________
2. Fossil Records - _______________________________________________________________
______________________________________________________________________________
3. Glacial Till - __________________________________________________________________
______________________________________________________________________________
4. Paleomagnetism - _____________________________________________________________
______________________________________________________________________________
a. Magnetic fields were __________________________on opposite sides of oceanic ridge.
5. Satellite imagery - _____________________________________________________________
______________________________________________________________________________
E. Cross Section of Earth
1. Understanding plate tectonics starts with knowing Earth’s basic _______________________.
2. If you could slice through our planet, you’d find it is made up of ___________ major layers.
a. ______________ – made of iron and nickel; inner core is solid and outer core is liquid.
b. _________________________ – made of rock; moves like toothpaste
c. _________________________– oceanic crust forms the ocean floor; continental crust
forms the continents
3. Lithosphere - _________________________________________________________________
______________________________________________________________________________
4. Asthenosphere - ______________________________________________________________
______________________________________________________________________________
5. Lithosphere is broken up into huge rocky slabs called ____________________________
____________________.
6. These plates are _______________________. They ride along the top of the asthenosphere.
F. Tectonic Plates
1. Continental plates are mostly comprised of ________________________________________.
2. Oceanic plates are mostly comprised of ___________________________________________.
G. Tectonic Plate Diagram - Use Page 7 in the textbook to label the tectonic plates below.
H. Convection – How do these huge slabs of Earth’s crust (a.k.a. tectonic plates) __________________?
1. Diagram
2. Convection - _________________________________________________________________
______________________________________________________________________________
Example - Soup that is heated from below rises. When it reaches the top of the pot it moves
outward, cools slightly, then sinks downward along the sides of the pot. When it reaches the
bottom, it’s heated up again and process repeats.
I. Plate Boundaries
1. _________________ ______________________ are places where two or more plates meet.
2. Scientists give the plate boundaries different names based on the _____________________
of the plates.
3. Divergent Boundaries – occurs where plates are moving _________________ and new crust
is being formed.
a. Oceanic – Oceanic - _____________________________________________________
________________________________________________________________________
Example: _______________________________________________________________
b. Continental – Continental - _______________________________________________
________________________________________________________________________
Example: _______________________________________________________________
4. Convergent Boundaries – occurs where two or more plates are coming together or
_________________________________.
a. Oceanic – Continental - __________________________________________________
________________________________________________________________________
Example: _______________________________________________________________
b. Oceanic – Oceanic - _____________________________________________________
________________________________________________________________________
Example: _______________________________________________________________
c. Continental – Continental - _______________________________________________
________________________________________________________________________
Example: _______________________________________________________________
d. Transform Boundary - ___________________________________________________
________________________________________________________________________
Example: _______________________________________________________________
II. The World Ocean
A. Oceans cover _________________________ of the Earth.
B. Ocean Floor