Transcript Plate Tectonics

California Earth Science
Standards
California Earth Science
Standards
Standard 3
Plate tectonics,
operating over
geologic time,
has changed
the patterns of
land, sea, and
mountains on
Earth’s surface.
Part 1
In this section, we
will cover the types
of Earth’s crust,
those rocks
associated with
each type, the
causes of plate
motion and the
types of plate
movement.
Please add the following
terms to your Standard 3
vocabulary booklet.
basalt
granite
oceanic crust
continental crust
convection
BasaltDefinition: A dark, volcanic ocean rock.
Similar Words: basal
GraniteDefinition: A hard, speckled igneous rock.
Similar Words: granitic
Oceanic CrustDefinition: The thin part of the earth's
crust found beneath the ocean.
Similar Words: ocean
Continental CrustDefinition: The thick part of the
earth's crust that makes up the land.
Similar Words: continent
ConvectionDefinition: The circulation of currents
in which warm areas rise and cool
areas sink.
Similar Words: convection oven
During this lesson, please
complete “The Story of Plate
Tectonics” worksheet.
Once upon a time, there was a great
planet called Earth.
Its surface was covered by 2
types of crust.
1
2
One type, which was below the oceans,
was thin and dense. It was known as
oceanic crust.
1
It was often composed of basalt.
The other, which covered the land, was
thick, yet not as dense. It was known as
continental crust.
2
It was often composed of granite.
A
B
Prepare to answer the following
multiple choice questions:
C
D
The 2 types of crust that surround
the Earth are known as:
A.
B.
C.
D.
pie crust and pizza crust
interior and exterior crust
continental and oceanic crust
upper and lower crust
The 2 types of crust that surround
the Earth are known as:
A.
B.
C.
D.
pie crust and pizza crust
interior and exterior crust
continental and oceanic crust
upper and lower crust
Which is the most dense?
A.
B.
C.
D.
granite
basalt
sea water
air
Which is the most dense?
A.
B.
C.
D.
granite
basalt
sea water
air
Granite and basalt are both
classified as:
A.
B.
C.
D.
magma
Igneous rocks
Sedimentary rocks
Metamorphic rocks
Granite and basalt are both
classified as:
A.
B.
C.
D.
magma
Igneous rocks
Sedimentary rocks
Metamorphic rocks
Going back to the story of plate
tectonics ...
These 2 types of crust made up the
upper portion of the lithosphere.
It was cracked into several pieces called
plates, which were constantly moving
around and bumping into each other.
The movement of these plates was
caused by convection currents.
Click to see how convection works.
Convection is a process which
results from differences in
temperature.
As materials become warmer,
they expand and become less
dense.
This makes them rise.
Materials that are cooler are
more dense and therefore sink.
Convection within the Earth
occurs because the core is
heated by radioactive decay.
As this heat makes its way
towards the surface ...
... some areas become warmer
than others.
The warmest areas rise ...
... while the coolest areas sink.
This is what causes the plates
to move.
In some places these plates
move away from each other, as
in the drawing above.
In other places, these plates
move toward each other.
In still other places, plates move
side by side, past each other.
Watch the convection currents
demonstration.
End of Part 1