Download Plate Tectonics Study Guide

Plate Tectonics Study Guide
1. What is the layer of Earth called that’s made up of the rocks basalt and granite?
2. As you go deeper beneath Earth’s surface, what happens to the temperature and
pressure beneath the surface?
3. How do geologists study Earth’s interior?
4. List the layers of the Earth starting at the
surface and going towards the center.
5. What is ridge push?
crust
It increases
Seismic waves
Crust, mantle, outer core, inner core
oceanic crust slides downhill under the
continental crust due to gravity
6. What is slab pull?
oceanic crust is denser than
continental crust, so it pulls the rest
of the plate with it as it sinks into the
mantle
7. Where are the convection currents located that move Earth’s plates?
The Athenosphere
8. What is a convection current?
the movement of heat energy throughout
a fluid caused by differences in
temp/density
9. What happens to convection currents when the heat source is removed?
they stop
10. What does Wegener’s theory of
continental drift state?
All continents have once been joined together and have
since drifted apart
11. What is the name of the super continent that existed millions of years ago called?
Pangaea
12. What do we call any trace of an ancient organism preserved in rock?
fossil
13. What are the three categories of evidence
Landforms, fossils, ancient climates
Wegener used to support his theory of continental
drift?
14. Why was Wegener’s theory rejected by
No explanation of the force that moved the
geologists of his time?
continents
15. What do we call the longest chain of mountains in the world?
Mid-ocean ridge
16. In the mid-1990’s what technology did scientists use to map the ocean floor?
Sonar
17. In sea-floor spreading where on the ocean floor
At the mid-ocean ridge
does molten material erupt onto the ocean floor?
18. What were scientists able to determine by
taking drilling samples of the ocean floor?
The age of the rocks at the center of the
ridge were youngest
19. What did deep diving submersibles observe at the mid-ocean ridge?
Pillow lava
20. What is the term used to describe ocean floor sinking into a deep-ocean trench?
subduction
21. As new oceanic crust cools, what happens to its density?
It increases
22. What is the force that causes Earth’s plates to move?
Convection currents in the
asthenosphere
23. What is the name of the theory that states that
Plate Tectonics
Earth’s plates are in constant slow motion?
24. What do we call a boundary where two plates collide?
25. If two continental plates collide, what is produced?
26. What do we call a boundary where two plates slip past one
another?
27. What type of rock primarily makes up oceanic crust?
28 What type of rock primarily makes up continental crust?
29. What is the name of the boundary where two plates
are moving away from each other?
30. What happens to a plate, as it is subducted into the mantle?
Convergent Boundaries
mountain ranges
transform boundaries
Basalt
Granite
divergent boundaries
It melts and returns into
magma.
31. What type of boundary occurs at a subduction zone?
Convergent boundaries
32. What geologic feature is formed at a divergent boundary?
Mid-ocean ridge/rift valley
33. What is being created at a mid-ocean ridge?
Mountain chains/ new crust
34. Describe the crust:
very thin, solid layer, least dense, coolest, upper
35. Describe the mantle:
67% of Earth’s mass, rock is soft (plastic/putty
like), pressure, density, temperature increase as
you go deeper. Convection currents here drive
plate tectonics
36. Describe the core:
33% of mass, deepest, densest, hottest layer. Has
two parts, inner and outer.
37. What is the lithosphere?
Crust and rigid part of the mantle. Divided into
tectonic plates.
38. What is the asthenosphere?
“Plastic” layer of the upper mantle. Tectonic plates
float on this layer.
39. What is the mesosphere?
Strong, lower portion of the mantle
40. What is the outer core?
Liquid iron and nickel, spins rapidly to create the
Earth’s magnetic field
41. What is the inner core?
Solid iron and nickel
42. What was Rodinia?
Super-continent before Pangaea
43. Where is old crust destroyed?
subduction zone
44. Where is new crust created?
mid-ocean ridge/rift valley
45. Describe the three ways
mountains are formed:
 Folded mountains: squeezed together (converging
boundary) and forced upwards (Alps, Himalayas)
 Fault block mountains: Caused by tension (diverging
boundary) causes areas to drop down relative to
other rocks. Makes these other rocks higher.
 Volcanic mountains: usually at convergent zones
where old crust is subducted. Create ranges of
volcanic mountains or island arcs of volcanic islands.
Draw a Convergent Boundary
Draw a Transform Boundary
Draw a Divergent Boundary