Blue Notes Outline

1. Name ___________________________________ Earth Science
Dynamic Crust-Earthquakes & Earth’s Interior Unit 3
I. LOCAL EVIDENCE OF CRUSTAL MOTIONS:
A. ________________________ & _________________________wears down the Earth’s crust.
_________________________ ____________________________ creates new mountains.
B. Sedimentary beds are deposited as _________________________ _______________ or
_______________________________
C. Evidence of motions within the Earth’s crust is indicated by: label the diagrams
1. ______________________
2. _____________________
3. _____________________
D. _______________________________________ provide direct evidence of crustal movement.
____________________ _________________ and ________________ __________________
are two changes that can be observed after an earthquake.
E. ______________________ ____________________ are used in mapping surveys and indicate
exact positions and elevations. Changes in ______________________ of benchmarks are evidence
that the land is either ____________________________ or ______________________________.
F. Displaced fossils found in mountains have 2 interpretations:
1. ______________________________________________________________________________
2. ______________________________________________________________________________
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2. G. _________________________________ is the RISING OF THE CRUST
_________________________________is the SINKING OF THE
II. EARTHQUAKES:
A. Two processes that cause earthquakes:
1. The movement of _________________________ inside ___________________________.
2. _______________________ is the movement of rock along a surface where the rocks are broken.
B. ___________________ movement of the crust over long periods of time builds _______________
within the rocks. Increased pressure causes the ___________________ ______________________
to break creating a _________________________. When faulting occurs energy radiates through the
Earth as __________________ ________________ that cause the ground to ________________.
III. MEASURING THE EARTHQUAKES:
A. There are 2 scales to measure earthquakes
1. ____________________________________
2. ____________________________________
B. _________________________________ scale is based upon the observations of people and the
damage caused. It measures the ____________________ of the earthquake from ______ to ______
C. _________________________ uses the seismograph to determine the _____________________
Magnitude is the total _______________________ released by the earthquake.
It’s numerical scale is _________ to _________. Each numeric step represents a _______ increase.
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IV. PARTS OF THE EARTHQUAKE:

3. A. The place underground where the break or fault occurs is the
_____________ of the quake
The _________________________ is the location along the
surface of the earth just above the focus where the quake is felt most strongly
A. The two most important energy waves are:
____________________________________________
____________________________________________
B. Characteristics of P-waves (primary)
_________________________________________________
_________________________________________________
_________________________________________________
_________________________________________________
C. Characteristics of S-waves (secondary)
___________________________________________________
___________________________________________________
___________________________________________________
___________________________________________________
D. Both S and P waves travel FASTER through ____________________ material.
V. FINDING THE EPICENTER:
A. The seismograph records the _____________________________ and
________________________________________________________________________________
(Use the chart on page 11 of your reference table)
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4. Use you Find the
Reference best fit
Table on the curve
page 11 Mark off the difference in and read the
arrival time distance
of S and P waves on a below
piece of
paper
B. The steps for calculating your distance from the epicenter:
1. ______________________________________________________________________________
2. ______________________________________________________________________________
3. ______________________________________________________________________________
4. ______________________________________________________________________________
Practice Questions:
1. The arrival of the P-wave is 12:03:00 The arrival of an S-wave is 12:07:00
The difference is _____________________
How far is this earthquake from this seismic station? ____________________
2. The arrival time of the P-wave is 2:05:00 The arrival time of the S-wave is 2:08:00
The difference is: _____________________
How far is this earthquake from the seismic station? _______________________
3. If the difference in arrival time between P and S waves is 2min. 35 sec. What is the distance
from the earthquake to the seismograph station? _________________________
4. How long does it take for a P-wave to travel from the focus of an earthquake to a seismograph
station 2,000 km. away? _______________________________
How long will the S-wave take to travel to this same station? ______________________
5. What is the difference in arrival time between P and S waves for an earthquake that is
5,000 kilometers away from the seismograph station? ______________________________
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5. VII. THE ORIGIN TIME OF AN EARTHQUAKE:
A. An earthquake wave detected at __________________________ times by observers at
____________________ distances from the epicenter.
B. To find the origin time seismologists need to know:
1. _____________________________________________________________________
2. _____________________________________________________________________
Example:
A seismograph recording station located 5,700 kilometers from an epicenter.
It receives a P-wave at 2:45 P.M.
At what time did the earthquake actually occur at the epicenter?
VIII. THE LAYERS OF THE EARTH:
A. The crusts thickness ______________________.
It is __________________ under the oceans
and ____________________ under the continents.
Continental crust is mostly ____________, __________ density & _________________________
The ocean basins are mostly ______________ and ________________ or __________________
B. Inferred characteristics of the Earth’s Interior:
1. Studying the ____________________________ of
______________________ _________________
allows us to make inferences about the structure
and composition of the Earth’s interior.
2. The _______________________ of a seismic wave changes with the ________________ of
the material it travels through. Waves are also ___________________________________
as they travel through materials with different densities.
We know that P-waves can be transmitted through ___________ __________ & ___________
S-Waves can be transmitted through ONLY ________________
3. Earth Quake Shadow Zones:
When an earthquake occurs both ____________ are received from most of the earth.
Opposite sides of the earth where the epicenter is, receives ____ but NO _______ because
S-waves cannot penetrate the ________________ outer core.
______________________ (bending) occurs at the __________________ ( boundaries)
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6. Draw a diagram of the earth’s interior and label and describe each layer or part:
A- Inner Core:
B- Outer Core:
C- Moho:
D- Mantle:
E- Crust:
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