I.
Earth Structure
A.
Inner Core
____________(phase of matter); _______________ km
diameter
Mostly Ni and Fe
Why is it solid even though it’s hot enough to melt
any rock? _____________________________________________
_____________________________________________________
_
B.
Outer Core
_____________/ Liquid; __________________ km thick
Mostly Ni and Fe
C.
Mantle
__________________ km thick;
Made of ________________ distinct layers:
1.
Mesosphere
Most of Mantle
Non-Newtonian ________________________
2.
Asthenosphere
Liquid/ ___________________
Mohorovicic Discontinuity
(AKA: ________)- where seismic waves slow down
3.
D.
___________ Lithosphere
Broken Solid/ brittle
Crust
Solid;
broken into pieces called ______________________
Mostly silica (________________)
rigid, with some flexibility
1.
Two types of crust:
a.
____________________ Crust
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More dense of the two; about ________ km thick
Basaltic composition (_______________ chemistry)
b.
_______________________ Crust
Less dense; more silica; about _________ km thick
Granitic composition (_______________
chemistry)
II.
Do Plates really move?
Past/ Indirect Evidence of Plate _____________________________
A.
Distorted _________________ Layers
1.
Folding & Tilting
a.
Principle of _____________________
Horizontality
B.
b.
________________________________
c.
Anticline
d.
Geosyncline
______________________________ Evidence
1.
Marine ____________________ found on the East Coast
of South America and West Coast of Africa; unable to
swim across the open ocean
2.
_____________________
What do corals need to survive? ____________________
_________________________________________________
Why are they found in Wisconsin? __________________
_________________________________________________
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3.
Ammonites & Belemnites in ______________________?
4.
Marine ___________________ on top of the Himalayas?
III. Present/ Direct ____________________________ of Plate
Tectonics
A.
________________________________
B.
________________________________ structures
like fences, buildings, rivers
C.
________________________________
IV. So the Plates move, How do they do it?
A.
V.
__________________ Currents in the _________________
The Physics of Plate Tectonics
A.
_________________________ acting on the crust
1.
__________________________ Forces
a.
Push or pull away from each other along a
single line of motion
b.
2.
Divergent _________________________/ Rift
__________________________ Forces
a.
A push towards one another in a single line
of motion
b.
Convergent _____________________________
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Orogeny (______________________ building)
1.
3.
Subduction ___________________
__________________________ Forces
a.
Forces that act in opposite directions along
different lines of motion. Like a ____________________
b.
__________________ sliding past one another
VI. So the Plates move, WHAT Happens now?
Joints VS. Faults; Landforms; Earthquakes
A.
Diastrophism the process by which the earth’s
surface is ______________________ by movement of the crust
B.
Jointsare breaks or _________________ in bedrock along
which NO movement has taken place
C.
Faults-
are breaks or fractures in bedrock along
which movement ______________________ taken place
1.
Parts of a Fault
a.
Footwall- the underlying surface of
an inclined fault plane. Can act like a _______________
b. Hanging Wall- the ________________________
surface of an inclined fault plane
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D.
Types of Faults
1.
______________________ a fault in which movement is
parallel to the dip of the fault surface
FYI: ____________ is the angle and direction at which a
plane is inclined from horizontal
a.
________________ Dip-Slip
The hanging wall
block has moved ____________ relative to the footwall
b.
1.
Caused mostly by __________________ forces
2.
___________________________ boundary
Reverse _______________
The hanging wall
block has moved ________ relative to the footwall
2.
1.
Caused mostly by _______________________
2.
__________________________ boundary
Lateral or ________________________ A fault in
which the fault block movement is parallel to the strike
of the fault surfaces.
FYI: __________________ is the compass direction of a
line by the intersection of an inclined plane with the
horizontal plane
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a.
Mostly horizontal displacement, there is little
or no vertical movement
b.
3.
Caused by _________________________ forces
_________________________ a fault having both
strike-slip and dip-slip components, where plates move
away from each other
a.
Rifting and Sea Floor spreading result from
this kind of fault.
E.
b.
Caused by _____________________________ forces
c.
___________________________________ boundary
_______________________________ from Crustal Movement
1.
_____________________ defined as a mass of rock rising
more than 600 meters above the surrounding land
Relief: ___________________________________________
a.
Fold _____________________ usually made mostly
of sedimentary rock folded by compression.
World’s tallest and most common mountains
1.
Examples: Appalachians, Rockies,
Alps, Himalayas
b.
Fault-Block _____________________formed by a
series of Normal Dip-Slip faults.
Some of the greatest mountain Ranges
1.
Examples: Sierra Nevada (California), Grand
Teton (Wyoming),
Wasatch (Utah)
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F. When the Earth Shakes________________________________
1.
Can be caused by _______________ eruptions, but more
often, faulting...
a.
__________________the movement of rock along a
fault
b.
__________________________ Rebound occurs
when tremendous pressure causes plates to move
and the rock layers shake back and forth
1.
_______________________ Waves are waves
of vibrations sent out in all directions from the
focus
2.
3.
Where do Earthquakes start?
a.
___________________ the point below the surface
where the rocks break and move
b.
___________________ the point on the surface,
directly above the focus
How are Earthquakes measured?
a.
____________________________ is an instrument
that detects, measures, and records the seismic
waves produced by earthquakes
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1.
Operates on Newton’s _____________ Law of
Motion
2.
4.
_______________________________ is the
recorded information and looks like a zig zag
line
Anatomy of a Wave
a.
Crest
the __________________ point on a
b.
Trough
the __________________ point on a
c.
________________________ refers to the
distance from the midpoint to the crest (or trough)
d.
__________________________ is the distance from
the top of one crest to the top of the next or the
distance between any successive identical part of
the wave
e.
Frequency
often called _______________, is the
number of vibrations (cycles) per second
wave
wave
5.
Types of Seismic Waves
a.
__________________ WAVES: are waves which
can travel through the body of the earth
1.
____________________ Waves AKA P-Wave;
are a type of Longitudinal wave. It causes back
and forth particle motion; it follows the same
direction as the energy transfer
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2.
a.
They are a type of ___________________
Wave (sound is this type)
b.
Will travel through solid, liquid, and
gas; must have a medium
c.
Travels 7.8 –8.5 km per second in the
Mantle…
7.2 km per second in _________________
crust...
3.5 km per second in continental crust
Secondary Waves AKA
_________________;
With these waves, the particle motion is
PERPENDICULAR to the direction of energy
transfer
b.
a.
Transverse or Shear wave
b.
Will travel only through _____________
c.
Travels 4 - 5 km per second
d.
Moves side to side like a _____________
_________________________ WAVES: move along
the surface of the earth only
1.
Surface Waves
AKA _________________
Travel through the crust of the earth and attenuate
(gradually disappear); Scientists have found that
attenuation occurs more slowly in older rock (like
the eastern US, but more quickly in younger rock
(western US)
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a.
They’re two main types: Love Waves
and Raleigh Waves and they will travel
only through _______________________
b.
Travels less than 4 km per second
c.
Moves up and down- causes most
___________________________________
_
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