Study Guide (Part 1)
Plate Tectonics
Key Vocabulary Terms for Part 1:

Continental Drift - _A hypothesis that Earth’s continents move on Earth’s surface.____
______________________________________________________________________________

Plate Tectonics - _The theory that the lithosphere is made of plates that move and
interact with each other at their boundaries. ____________________________________

Lithosphere - _The outer shell of the Earth consisting of the crust and uppermost
portion of the mantle. _______________________________________________________

Asthenosphere - _The partially melted layer of the mantle that underlies the lithosphere
___________________________________________________________________________

Crust - _The very thin outer layer of Earth above the mantle, composed of a rigid layer
of lighter rocks that can extend 65 kilometers at its deepest point ___________________

Mantle - _The thickest of Earth’s layers, located between the outer core and Earth’s
crust, composed mostly of compounds rich in iron, silicon, and magnesium. __________
Notes for Part 1:

What is the Lithosphere composed of (pg.73)? _The crust and the uppermost portion of the
mantle together ______________________________________________________________

What is the Asthenosphere and where is it located (pg.73)? _A thin, slushlike layer of the
mantle located below the Lithosphere ____________________________________________

Where is the crust located and why does it matter to Plate Tectonics (pg. 73)? _The crust is
located on the uppermost portion of Earth’s surface and is associated with our plates ______

How does the Asthenosphere affect the Lithosphere in regards to Plate Tectonics (pg.73)?
_The Asthenosphere moves the Lithosphere, which drives Plate Tectonics _______________
Study Guide (Part 1)

Who was Alfred Wegener and what did he propose in 1912 (pg.172)? _A German scientist
who in 1912 proposed the hypothesis of Continental Drift ____________________________


What 4 pieces of evidence did Wegener use to support his hypothesis (pg. 172)?
o
Similarities in the shape of the continents
o
Fossil remains of Mesosaurus
o
Distinctive rock formations
o
Climate change evidence
Wegener’s hypothesis was not accepted because he had no evidence to explain… (pg. 172)?
_How the continents moved ___________________________________________________

What discoveries happened in the 1950s and 1960s added support for Wegener’s hypothesis,
but still did not explain how they moved (pg. 173)? _Earthquakes, magnetism, and the age of
rocks on the ocean floor _______________________________________________________

What theory did scientist come up with to explain the movement of plates (pg. 173)? _The
Theory of Plate Tectonics _____________________________________________________
Study Guide (Part 1)


What other 3 things did the new theory help explain geologically (pg. 173)?
o
Where earthquakes are likely to occur
o
Where volcanos are likely to occur
o
How new crust forms along the ocean floor
By looking at the magnetism of oceanic crust, what can they determine from it (pg. 174)?
_The age of the rocks ________________________________________________________

Where would you find the youngest and oldest rocks in regards to where they would be
located to at a mid-ocean ridge (pg.174)? _The youngest rocks would be located closest to
the mid-ocean ridge, while the oldest rocks would be located furthest from the mid-ocean
ridge _____________________________________________________________________