Download Geography 12

Chapter 6 Objectives:
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Geography 12 Key
Worksheet 6.2
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Lithosphere Plates: A Simple But Elegant Idea
Read pages 88 – 91 of Planet Earth: A Physical Geography. Answer
the following questions:
Vocabulary (1 mark each)
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Folding: the process that bends and twists rocks through compression or
squeezing
Faulting: the process by which rocks move past one another along a
fracture or cracking the earth’s crust, usually occurring where plates
are separating, sliding past one another, or colliding
Vulcanism: the movement of molten rock, or magma, beneath or above
the earth’s surface
Hot Spot: a point on the earth’s surface where strong upward convection
currents or plumes of hot magma in the upper mantle push up below the
plates of the lithosphere causing volcanic activity
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Appreciate the power and
scope of tectonic processes
and their effects
Appreciate the slowness of
tectonic processes based on
a human time scale
Understand that the
lithosphere is an everchanging part of a dynamic
planet
Understand the general
pattern of tectonic activity
over geologic time and
explain the location
pattern of tectonic activity
over the earth’s surface
Explain the tectonic
processes that shape the
earth’s surface, including
folding, faulting, and
volcanic activity
Describe and explain the
pattern of major surface
features created by tectonic
processes
Predict the nature and
general patterns of
occurrence of tectonic
activities and processes,
especially earthquakes and
volcanic eruptions
Describe the positive and
negative aspects of tectonic
activities
Converging plate boundary: the boundary between two plates that are moving towards
one another
Diverging plate boundary: the boundary between two plates that are moving apart or
separating, at a mid-ocean ridge
Transform plate boundary: the boundary between two plates that are slipping or sliding
past one another
Subduction zone: the zone where an oceanic plate is sinking below a plate containing
continents at a converging plate boundary
Short Answer (2 marks each)
1. How did scientists first come upon the theory of plate tectonics?
By looking at satellite imagery and plotting the locations of earthquakes, they were able
to find patterns. They realized large, moving plates collided and hence the theory of
plate tectonics was developed.
2. What causes earthquakes and why are some earthquakes major and others minor?
Movements in the crust trigger shock waves (earthquakes). Subduction zones release
the most energy and major earthquakes. Diverging plates release less energy and
minor earthquakes.
3. How are the Rocky Mountains believed different in origin than the Canadian
Shield?
They are not different. Both the Rocky Mountains and the Canadian Shield were
formed by subduction. The Canadian Shield is much older and weathered, but also has
stopped moving while the Rocky Mountains are still active movers
4. Briefly explain the difference between Converging, Diverging and Transform
Fault boundaries. (3 marks)
Converging…plates moving together (collide or slide under the other)
Diverging….plates separate from each other
Transform Fault….plates slide past each other
5. Describe the type of tectonic action that produced the Boxing Day Tsunami 2004
at Indonesia? What actually caused the Tsunami (or Harbour Wave)?
Converging …subduction. The Australian Ocean plate sunk below the Asian Plate.
When the Asian Plate was pushed up, it pushed the ocean water up (wave).
Here is a link to an internet lesson on Plate Tectonics you should read:
http://www.extremescience.com/PlateTectonicsmap.htm#Pacificplate