World Geography
Chapter 3
Ch.3 Plate Tectonics and Weather
Forces that change the earth’s surface

There are two major geological processes that create features on the earth:

__________ and _______ ___________

______________ and ____________

They both take a long time to change the earth.

Remember, nothing drastic on earth happens at human speeds.
Plate Tectonics
► Huge volumes of heated and molten rock moving around the earth’s
interior form massive solid plates that move extremely slowly across the
earth’s surface.

_________ _______: huge rigid plates that are moved with
convection cells or currents by floating on magma or molten rock.
Plate Movement

Tectonic Plates move in 1 on four ways.
o ___________, or moving apart
o ____________, or diving under another plate
o ___________, or crashing into one another
o Sliding past each other in a shearing motion
Earth’s major Tectonic Plates
The extremely slow movements of these plates cause them to grind into one
another at _____________ _______ boundaries, move apart at
__________ ______ boundaries and slide past at __________
_______ boundaries
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World Geography
Chapter 3
Ch.3 Plate Tectonics and Weather


The San Andreas Fault is an example of a __________ fault.
A ______ _____ is created when rocks meet and lack flexibility. They
crack under pressure and the fracture is called a _______.
Results of Movement
► ____________ are a result of plate movement.

The ________ Scale is used to measure the intensity of an
earthquake.
► _____________ can result from earthquakes originating in the ocean.
► ___________ are often located along the boundaries of tectonic plates.

Magma, gases, ash, and dust explode out of these vents in the
earth’s surface.

The ________ ____ __________ is located on the rim of the Pacific ocean
and contains most of the earth’s _______________.
Weathering
► ____________ is an external process that wears the earth’s surface
down.
► Three types of weathering:
 _____________
► Big Rock becomes Small Rock due to wind, rain, and frost
wedging.
► Frost wedging occurs when water freezes in between the
pores of large sedimentary rocks.
 _______________
► When a chemical reaction degrades or decomposes a rock.
► More common with rocks containing carbon and oxygen, like
limestone.
 ______________
► Conversion of Rock and Minerals into smaller particles due
to living thing.
► Lichens, Tree Roots, Earthworms.
Erosion
► Erosion is another major external factor that changes the surface of the earth.
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World Geography
Chapter 3
Ch.3 Plate Tectonics and Weather
► ___________ is different from weathering because erosion deposits
materials from one place to another.
► Four major examples of erosion:
► __________ _____________ and _____
► ______ __________
► __________ ___________
► ______ __________
Glacial Movement and Mass Wasting
► Glacial Movement

The movement of ___________ grind away mountainsides and
form basins to capture melted ice water.

The _______ _______ were formed using this method.
► Mass Wasting

When _______ and _______ masses become detached from
underlying material and move downhill under the influence of
gravity.
► Rockslides, Mudslides, and Landslides

Clearing of Trees and other vegetation increase Mass Wasting
Occurrences.
Water and Wind Erosion
► Water Erosion

Water picks up material and moves it ______ stream.

_______ can also reduce or increase beaches.
► Wind Erosion

Wind transports and deposits ____________.

Wind speeds must reach a minimum of ____ miles per hour before
sediment can be moved.
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