Download Name: Date: Period:____ Study Guide for Plate Tectonics Key 1

Name:__________________________
Date:______________ Period:____
Study Guide for Plate Tectonics Key
1. What is the theory of continental drift? Who was founded the theory?

Theory: the theory the continents were once a supercontinent that broke up into plate
and drifted apart. Founded by Alfred Wegener.
2. List 4 examples of evidence to support continental drift.

Landforms, Climate, Fossils from plants and animals, & sea-floor spreading
3. Explain sea-floor spreading. Where does this occur?

The process by which new oceanic lithosphere forms as magma rises towards the
surface and solidifies. It occurs at divergent plate boundaries & the mid-ocean ridge.
4. List the physical layers of the earth. Be able to describe their composition and whether
they are a liquid, solid, or gas.

Composition Layers: Crust, Mantle, & Core

Physical Layers: Crust, lithosphere, asthenosphere, mesosphere, outer core, & inner
core

See matrix for all composition and all layers are solid except outer core is a liquid (The
difference between density of the crust and the core is that the core contains more
iron, thus making it denser)
5. What is Pangaea? What is Laurasia? Gondwana?

Pangaea-supercontinent from continental drift; Laurasia (top half of supercontinent
once it broke into 2 parts; Gondwana- bottom half of supercontinent)
6. Describe the boundaries (convergent, divergent, & transform)

Convergent-collides
o Continental-Continental ~ collision creating mountains (ex: Himalayas)
o Oceanic-Oceanic ~ denser plate subducts (creates island arcs)
o Oceanic-Continental ~ oceanic plate subducts (creates volcanoes on land)

Divergent- separates

Transform-slide past one another
7. Convergent-collides & produces earthquakes
o Continental-Continental ~ mountain ranges (ex: Himalayas)
o Oceanic-Oceanic ~ creates island arcs
o Oceanic-Continental ~ creates volcanoes on land

Trenches always occur at subduction zones

Divergent- Mid-Ocean Ridges & Seafloor Spreading; Volcanoes & Earthquakes

Transform-Earthquakes
8. What is subduction? Where does it occur? Where do mountains form?

Subduction- when one plate, the denser plate, slides up underneath another plate. It
occurs at convergent boundaries that are continental-oceanic and oceanic-oceanic.

Mountains are formed from convergent boundaries that are continental-continental.
9. What is magnetic reversal? What does it help support?

Magnetic reversals are when the magnetic poles change places. It helps support seafloor spreading.
10. What are the three types of faults?

Normal, Reverse, & Strike-Slip
11. What type of stress causes each type?

Normal fault- stress by tension; Reverse fault- caused by compression; and strike-slip
fault (not caused by either)
12. What is the relationship between a footwall and a hanging wall?

Normal fault-the hanging wall moves downward

Reverse fault- the handing wall moves upward
13. How do we map the interior of the earth?

Seismic waves
14. Convergent Boundary
Divergent Boundary
Transform Boundary
15. A Convection Current is the continued heating & cooling of molten rocks that drives the
movement of tectonic plates. It occurs in the asthenosphere.