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Ch 13-15 Plate tectonics, Volcanoes & Earthquakes
I. ___________________________ – study of the movement of the plates of the Earth’s surface
A. Lithosphere – _________________________________________________________
________________________________________________________________________
 ocean plates are made of __________________
 continent plates are made of ________________
B. Asthenosphere

_________________________________________________________________
 part of the mantle that has ____________________________________________ enabling plates to ___________________________________________________
II. Evidence for Plate Tectonics
1. Similarities in the ____________________________________, they look like
____________________________________
2. Fossil remains of _______________________________ are only found in _________,
South America & in
_________________________________
3. Specific _____________________ on Africa &
South America where they seem to _______
A. Alfred Wegener – _____________________
________________________________________
________________________________________________________________________
________________________________________________________________________

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III. Plate boundaries –

Areas where plates _______________________________________________________

________________________________________________________________________
 largest belt is called the ____________________________________________________

3 Types of Plate Boundaries
1.
_____________________________________
2.
_____________________________________
3.
_____________________________________
A. Converging Boundaries
(_____________________________)
2 Types of Converging boundaries: a. ______________________________________ b. ______________________________________
1. Collision – _______________________________________________________
__________________________________________________________________ a. ____________________ – formed from India & Eurasia crashing together b. ________________________________ - formed 300 million yrs. ago by
a collision between Europe & Asia c. ___________________________________
between North America & Africa
– formed by a collision
2. Subduction – _____________________________________________________
__________________________________________________________________

3 a. O-O subduction results in a trench & island arc
Ex. #1. Pacific Plate under the Philippine Plate: forms the
_____________________________________________
#2 Pacific Plate under the Eurasian Plate: forms the
___________________________________________________ b. O-C subduction : results in trench & coastal mountains
Ex. #1Nazca Plate under the South American Plate: forms
_____________________________________
#2 Juan de Fuca Plate under the North American
Plate: forms _______________________________
______________________________________________
B. Diverging Boundaries (________________________)

___________________________ is on the _________________

_____________________________________________________________
_____________________________________________________________
1. _________________
N. American & Eurasian
Plates are parting; Iceland
2. _________________
Pacific & Nazca Plates are parting

C. Sliding Boundaries (__________________)
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1. ________________________________________________________________
_____________________________________________________________
IV. Craton – _________________________________________________________________
3 Sources of Material Added to the Continent
1. _________________________________________
2. _________________________________________
3. ____________________________________ at O-C plate boundaries ocean sediments
______________________________________________________________________
at subduction zones
V. _____________________ Princeton University

_______________________________________________
____________________________________ in the mantle is forced ________________
______________________________________________________________________
 the sea floor is carried away from the ______________ as the new material flows
____________________________________

________________________________, becomes _______________________ then the layer below it & sinks a bit to form a _____________________

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Evidence for Sea Floor Spreading
1. Age Evidence – _________________________________________________________
______________________________________________________________________
2. Magnetic Clues - in iron bearing basalt rock of ocean floors

Sea floor rocks show _________________________
__________________________________________

Magnetic alignment of
________________________________ & forth parallel to the mid-ocean ridges
VI. Causes of Plate Tectonics
A. Convection Currents – __________________________________________________
B. Differences in rock density ; _______________________________________________
VII Earthquakes
Earthquake - the shaking of Earth's crust caused by a release of ________________; vibrations made from _____________________
A. Forces Inside the Earth
Elastic Rebound Theory
1.
_________________________________
_________________________________
2.
_________________________________
_________________________________

3.
stress overcomes ____________________ & plates move suddenly because rocks have bent & stretched until they have _________________________
Results : ____________________________________________________________;
Earthquake
B. Fault

______________________________________________________

Rocks move in __________________________________________________
C. ________________ - place inside the
earth where the quake actually occurs
D. _________________ - pt. On Earth's
surface directly above the focus of the
quake
E. 3 Forces Rocks Experience
1. _______________________________ - stress that squeezes compacts
2. _____________________ - stress that causes stretching & elongation
3. _____________________ - force that causes slippage & the rocks on
either side to move past each other
VIII. Earthquake Information
A. _______________________________ - energy waves that move outward
from the earthquake focus & make the ground quake
B. 4 Types of Seismic Waves
1.
___________________________________________ (P-wave)
2. ____________________________________________ (S-wave)
3.
____________________________________________ (L-wave) a. ____________________________________________ (L-wave) b.
____________________________________________(L-wave)
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C. Primary waves - _______________________________________________
____________________________________________________
* ____________________________________________
* ____________________________________________
D. Secondary wave - _____________________________________________
E. Surface waves (___________________________________) - waves that
travel like ripples on a pond across Earth's surface

__________________________________________
 particles move in an elliptical motion, as well as ____________________

___________________________________________________________

___________________________________
Two examples of Surface Waves ___________________ & _____________________
IX. Locating an Earthquake

Seismograph - _________________________________________________ o Readings from _____________________ are needed to locate the _____________ o ____________________________________ o The more _______________________________, the _____________________
the epicenter is o _________________________________________________________
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A.
Richter Scale - the measure of the ___________________________________________, each ____________________________________________
B.
Moho Discontinuity - ______________________________________________________
 seismic waves ___________________ because they are passing through a
_______________________
IV. Seismology - ________________________________________
A. Seismologist - _________________________________________
B. Seismograph - ___________________________________________
C. Tsunami - ________________________________________________
V. Volcanoes
___________________ vent in the Earth’s surface that often forms a mountain when layers of lava & volcanic ash erupt & build up
A. What causes a Volcano? (3 things)
______________________________________________________
______________________________________________________
______________________________________________________

______________________________________________________
B . Vent – opening in Earth’s surface where molten rock comes out
C. ______________________– steep walled depression around a
volcano’s vent
D. _______________________________ – areas where magma
from deep in Earth’s mantle has melted through the crust to
form several volcanoes
1. Ex. ___________________________________________ the Pacific Plate is moving over a stationary hot spot;
Kauai is the ___________________ & Lo’ihi an underwater volcano will form the next island in the chain
E. _____________________– formed when the top of a volcano collapses into the partially emptied magma chamber, producing a large opening
Ex. _____________________________________
VII . Plutons – igneous rock(_________________________) that cools inside other rock
Types:
1. Dikes – __________________
___________________________
___________________________
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2. ____________________________– largest igneous intrusions, forms when magma cools underground before reaching the surface
3. Sills – __________________________________________________
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__________________________________________________________
4. ____________________________________– domed sill, that has pushed up the rock above it ex. __________________
_____________________
5.
____________________________ – the hard solid vent of a volcano left behind after the cone erodes
Ex. ______________________________________________
_________________________________________________