Download Plate Tectonics Review Guide new lithosphere

Name: ________________
Date: ___________ HR: ___
Plate Tectonics Review Guide
1. Explain sea floor spreading. At what type of plate boundary does it occur at?
new lithosphere forming from magma rises at a mid-ocean ridge. It solidifies to create not oceanic lithosphere.
It creates new crust and spreads equally at both sides
2. Describe Wegener’s idea of continental drift.
A hypothesis that states continents move and were once part of one big landmass. It was later confirmed by
evidence of sea floor spreading.
3. List 5 pieces of evidence to support the idea of continental drift. Which piece of helps explain how
plates move.
Fossils
Rock formations
Climatic evidence
Mid-ocean ridges & Seafloor Spreading
Paleomagnetism
4. Describe a mid-ocean ridge.
an undersea mountain range at a divergent boundary
5. What is a rift?
crack in the middle of a mid-ocean ridge in the center of the “rift valley”
6. Explain the Theory of Plate Tectonics.
the theory that explains why and how continents move.
7. True or False? Tectonic plates can include both continental and oceanic crust.
True
8. What type of rock is commonly formed at convergent boundaries:
•
•
continental-continental - Metamorphic
continental- oceanic – igneous and metamorphic
9. Fill in the following chart:
Divergent
Type of crust
involved
Convergent
Oceanic-oceanic
oceanic
Transform
Continental
Oceanic-continental
Continental-continental
Description of
what happens
Draw a sketch
with arrows
showing
movement at
this boundary
Plates are moving away from
each other
Plates are colliding
Plates are sliding past each
other
What
landforms/
features
o-o = island arc
o-c = trench, volcano
Mid-ocean ridge
c-c = mountains (metamorphic
rock)
Mid-Atlantic Ridge
o-o = Japan
formed
Example/
Location
faults
San Andreas Fault
o-c = Mariana Trench
c-c = Himalayans
10. Compare and contrast the oceanic crust and the continental crust – be sure to include age,
thickness (size) and density.
Oceanic
Denser
Thinner
Mafic (iron and magnesium)
Younger
Continental
less dense
thicker
Felsic (silica)
Older
11. What is subduction? How does it happen?
Subduction occurs when the denser plate sinks underneath another plate.
12. The lightest materials on Earth are found in which layer?
The lithosphere
13. Draw and label the layers of the earth.
14. List and describe the three causes of plate motion.
Mantle Convection – heated material rises through the cooler denser material around it, as it rises the denser
material flows away from the hot material and sinks creating a conveyer belt for the lithosphere
Ridge Push – as the cooling rock sinks the asthenosphere below it exerts force on the rest of the plate which
creates a pushing motion.
Slab Pull – When the lithosphere is dense enough it begins to subduct into the asthenosphere and as the
leading edge of the plate sinks it pulls the rest of the plate along behind it.
15. Use the map below to answer the following questions, be able to answer questions using maps that
indicate types of plate boundaries:
16. What type of plate boundary is located between the Nazca Plate and the Pacific Plate?
Divergent Plate Boundary
17. What type of boundary is located between the Caribbean plate and the North American plate? Predict
what events may occur at this location as a result of the plate boundary.
Transform Plate Boundary
18. What type of crust makes up the African plate? Ocean and Continental Crust
19. Where do deep ocean trenches form?
At subduction zones – where one plate is sinking below another plate at a convergent plate boundary.
20. What is paleomagnetism? the study of alignment of magnetic minerals in rock, specifically as it relates
to earth's magnetic poles, this helped confirm wegner’s hypothesis and provided evidence for sea floor
spreading.
21. What is the pacific ring of fire?
The pacific plate – a ring of active volcanoes and earthquakes.
22. What do frequent earthquakes indicate?
A plate boundary is present in the area.
**Be able to label the direction of movement and crust involved for each type of plate boundary**