Transcript Plate Tectonic notes

Earth Science Picture of the
day
http://epod.usra.edu/
Unit 3 Dynamic Earth
At the end of this unit you will be able to
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Recall that the internal heat of the earth comes from radioactive
decay of materials and also residual heat from formation
State that differences in density within the earth cause the tectonic
plates to move
Infer properties of the earths interior based on seismic data
Recall the theory of plate tectonics, and the evidence to support it.
Know the three types of plate boundaries and their properties
Realize that the motion of plates causes: earthquakes, tsunamis, and
volcanoes
Know the three types of seismic waves and their properties
Analyze seismic waves to determine, origin time, travel time, lag time,
and distance to epicenter
Read and interpret graphs and charts in the reference tables to obtain
information about plate boundaries and earthquakes
Laboratory activities for this
unit
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Continental drift
Crustal Boundaries
Finding Epicenters
Location of an Epicenter
Location of an Epicenter #2
Ring of fire
In your table of contents please
add the following
Unit 3 Plate tectonics/Dynamic Earth
37-38 Vocabulary
39 Layers of the earth
40 Vocabulary
41-42 Theory of Plate tectonics
43 Sea Floor spreading
44 Convergent boundaries
45 Divergent boundaries- foldable
46 Transform boundaries- foldable
In your table of contents please
add the following
Unit 3 Plate tectonics/Dynamic Earth
47
Now turn to page 37 and number up to
page 49
On page 37 at the top please write:
Unit 4: Earth Interior vocabulary
You will be writing out 9 vocabulary
words, you may not need 2 pages,
but I gave you extra room in case
you did.
Page 37 in notebook
VOCABULARY
1. Crust: outermost portion of earth’s solid
lithosphere
2. Continental crust: crust that makes up the
continents, granitic and less dense
3. Oceanic crust: crust under the ocean,
basaltic and more dense
4. Lithosphere: whole crust together and the
upper mantle
5. Moho: interface between crust and mantle
Page 37, 38 in notebook
VOCABULARY
6. Asthenosphere: plastic upper portion of the
earth’s mantle that the plates move on
7. Mantle: layer between the crust and outer
core
8. Outer core: zone between mantle and inner
core, thought to be liquid because no S waves
travel through it
9. Inner core: solid, thought to be iron and
nickel based on meteorites and earth’s
magnetism
I. Layers of the earth
Page 10, ESRT
Page 39 in notebook
I. Layers of the earth
A. Crust (2 Types) Solid
1. Continental- low density,
2.7 g/cm3 , granitic
2. Oceanic- high density
3.0 g/cm3 , basaltic
Page 39 in notebook
I. Layers of the earth
B. Mantle – Solid, 3.4-5.6 g/cm3
1. What the plates move on
2. Plastic like
Page 39 in notebook
I. Layers of the earth
C. Outer Core – Liquid,
9.9-12.2 g/cm3
D. Inner Core – Solid,
12.8-13.1 g/cm3
1. Highest density layer
Practice questions
• What is the pressure at the inner core and
outer core boundary?
• What is the temperature at the outer core
and stiffer mantle boundary?
• What is the depth of the boundary
between the Asthenosphere and Stiffer
mantle?
• What is the thickness of the stiffer mantle
• What is the density of the oceanic crust?
Page 40 in notebook
VOCABULARY
• Tectonic plates: section of lithosphere that
moves, aka plates
• Convergent plate boundary: boundary
between two colliding plates
• Divergent plate boundary: boundary between
two plates that are moving apart, new crust is
created
• Transform plate boundary: boundary where
two plates slide past each other
Page 40 in notebook
VOCABULARY
• Mid-Ocean ridge: mountain range at the
bottom of the ocean where two plates are
diverging and creating new crust
• Ocean trench: deep valley produced when
two convergent plates collide in an ocean
• Subduction: one of the plates at a
convergent boundary sinks under the less
dense plate
Page 41 in notebook
II. Theory of Plate Tectonics
A.
Continental Drift
1. Proposed by Alfred Wegner
2. Continents look like they fit
together like a puzzle
Page 41 in notebook
II. Theory of Plate Tectonics
B. Evidence of Drift (Foldable)
1. Rocks match from
continent to continent
2. Mountain chains match
3. Fossils match
Page 42 in notebook
II. Theory of Plate Tectonics
C. Sea Floor Spreading
1. Oceans are getting bigger (Atlantic
Ocean)
2. caused by convection in the mantle.
3. Evidence
a. Rocks are younger at the ridges
and older as you travel away
Pangea: Hypothetical
landmass that existed 200
million years ago, where
all the continents were
joined.
II. Theory of Plate Tectonics
D. Plate motion
Page 43 in notebook
visualizations
1. Convergent Boundaries
a. Collision: destruction of crust
b. Types
1. Oceanic- Oceanic, Trench forms
2. Continental- Continental,
Mountains form
3. Oceanic- Continental, denser
plate sinks, Mountains chains along
the coast and a trench forms
II. Theory of Plate Tectonics
D. Plate motion
Page 44 in notebook
2.Divergent Boundaries (foldable)
a. Plates moving apart
b. New Crust is being made
c. Examples of locations: Mid
Atlantic Ridge, East Indian Ridge
II. Theory of Plate Tectonics
D. Plate motion
Page 45 in notebook
3.Transform Boundaries (foldable)
a. Plates are sliding past each other
b. Shallow earthquakes
c. Example: San Andreas Fault, CA
The Andes
Mountains
run along the
west Coast of
South
America
Page 46 in notebook
Earthquake VOCABULARY
• Earthquake: rapid and natural shaking of the
earth caused by movement of the tectonic
plates
• P-wave: Primary, first to arrive, fastest, travel
parallel to movement direction
• S-Wave: secondary, second to arrive, travel
perpendicular to wave direction
• Epicenter: place on the Earth’s surface
directly above where the earthquake
originated
Page 46 in notebook
VOCABULARY
• Focus: place where the earthquake
originated, underground
• Volcano: a mound of extrusive igneous rock
that erupts
• Tsunami: large wave created when an
earthquake occurs underwater
• Hotspot: a weak spot in the earths crust
where magma comes up through the crust,
typically in the middle of a plate
Page 47 in notebook
III. Earthquakes
1. Shaking or trembling of the ground
caused by motion of the plates
A. Types of earthquake Waves
Foldable….
III. Earthquakes
A. Types of Seismic waves
1.Primary
a. Fastest
b. Travels through, S, L, G
c. aka : Compressional waves
d. Travel parallel to vibration
III. Earthquakes
A. Types of Seismic waves
2. Secondary
a. slow waves
b. Solids ONLY
c. aka” Shear waves”
d. Travel perpendicular to
vibration
III. Earthquakes
A. Types of Seismic waves
3. Surface Waves
a. L- waves
b. cause all the damage
associated with the
earthquakes
Page 48 in notebook
III. Earthquakes
How do I….? (foldables)
…..Find lag time
1. Lag time is the difference
between the arrivals of the S and P
waves.
2. S arrival – P arrival = Lag time
3. On page 11 ESRT, it is the
space between the 2 lines
Page 48 in notebook
III. Earthquakes
How do I….? (foldables)
….Find The travel time of the waves
1. What wave are you solving for? P or S?
2. Using pg 11 ESRT
3. Knowing the distance to the epicenter,
go up to the wave you are solving for.
4. Read over to the Y axis for the time.
Page 49 in notebook
III. Earthquakes
How do I….? (foldables)
Find the distance to the epicenter?
1. Calculate the lag time
2. Using pg 11 ESRT, take a piece of scrap
paper and place it along the Y axis, mark the
zero and the lag time you calculated.
3. Slide the scrap up the graph until the 2
marks you made touch the P and S waves.
(slide and match)
4. Read down to the x axis for the
distance.
Page 49 in notebook
III. Earthquakes
How do I….? (foldables)
Find the time when the earthquake
happened (origin time)?
1. Knowing the P arrival time from the
seismograph.
2. subtract the Travel time for the P
wave for the distance calculated for that
location.
3. Origin time= P arrival – P travel