I need to complete both these labs by Friday afternoon Western Time.
Geology 4
Dr. Hall
Dating and Structure
Name ________________________________________
1) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
6. ______
5. ______
4. ______
3. ______
2. ______
1. ______
Oldest
2) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
5. ______
4. ______
3. ______
2. ______
1. ______
Oldest
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Geology 4
Dr. Hall
3) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
7. ______
6. ______
5. ______
U
4. ______
3. ______
2. ______
F
1. ______
Oldest
4) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
7. ______
6. ______
5. ______
4. ______
3. ______
2. ______
1. ______
Oldest
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Geology 4
Dr. Hall
5) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
9. ______
8. ______
7. ______
6. ______
J
5. ______
4. ______
3. ______
2. ______
1. ______
Oldest
6) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
8. ______
7. ______
A
6. ______
5. ______
4. ______
3. ______
2. ______
1. ______
Oldest
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G
Geology 4
Dr. Hall
7) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
7. ______
6. ______
5. ______
G
4. ______
3. ______
H
2. ______
1. ______
Oldest
8) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
12. ______
11. ______
10. ______
9. ______
8. ______
7. ______
6. ______
5. ______
4. ______
3. ______
2. ______
1. ______
Oldest
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Geology 4
Dr. Hall
9) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
16. ______
15. ______
14. ______
13. ______
12. ______
11. ______
10. ______
9. ______
8. ______
7. ______
6. ______
5. ______
4. ______
3. ______
2. ______
1. ______
Oldest
10) Different types of isotopes are defined based on their number of _______________ .
A. Electrons
B. Neutrons
C. Protons
D. All the above
11) Different types of atoms are defined based on their number of _______________ .
A. Electrons
B. Neutrons
C. Protons
D. All the above
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X
Geology 4
Dr. Hall
12) Instructions: List, from oldest to youngest, each of the rock units and geologic events in the
diagram below. Be sure to include all brittle and ductile deformations, unconformities, and
plutons and identify what kind they are.
Youngest
17. ______
16. ______
15. ______
14. ______
13. ______
12. ______
11. ______
10. ______
9. ______
8. ______
7. ______
6. ______
5. ______
4. ______
3. ______
2. ______
1. ______
Oldest
13) What is known as two protons and two neutrons released from the nucleus of an atom?
A. Gamma radiation
B. Alpha particle
C. Beta particle
D. All the above
14) What is released from a neutron in the nucleus of an atom, causing it to become a proton?
A. Gamma radiation
B. Alpha particle
C. Beta particle
D. All the above
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Geology 4
Dr. Hall
15) Protons are larger and heavier than electrons, reside in the nucleus of an atom, and have a
negative charge.
True
False
16) _____________ create layers that can be used for dating and creating timescales.
A. Tree Rings
B. Corals
C. Ocean Sediments
D. All the above
17) Mountain Matching:
_____ Compression
A. material is permanently deformed
_____ Tension
B. material returns to its original shape
_____ Shear
C. pushes from opposite directions
_____ Elastic
D. material breaks or fractures
_____ Ductile
E. pushes from opposing directions
_____ Brittle
F. pulls from opposite directions
18) Instructions: Draw with shading the amount of Uranium that would be present at each stage
after 0, 1, 2, and 3 Half Lives. Fill in the blank, given a Half Life of 250,000 years, how old is
this rock after each of the Half-Lives?
Half Life = 0
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Half Life = 1
Half Life = 2
Half Life = 3
GEOL4
Dr. Hall
Earthquakes
Name ____________________________
Introduction: Earthquakes occur because of a sudden release of stored energy. This energy has
built up over long periods of time because of tectonic forces within the earth. This sudden
motion causes seismic waves to radiate from their point of origin called the hypocenter and
travel through the earth. It is these seismic waves that can produce ground motion which people
call an earthquake. Seismic waves can travel far and can be detected by sensitive scientific
instruments called seismographs.
Seismic Waves: A seismic wave is simply a means of transferring energy from one spot to
another within the earth. Although seismologists recognize different types of waves, we are
interested in only two types: P (primary) waves and S (secondary) waves. Within the earth, Pwaves can travel through solids and liquids, whereas S-waves can only travel through solids. The
speed of an earthquake wave is not constant but varies with many factors. Speed changes mostly
with depth and rock type. P-waves travel between 6 and 13 km/sec. S-waves are slower and
travel between 3.5 and 7.5 km/sec.
Seismograms: A highly simplified simulated recording of earthquake waves can be seen in
Figure 1. Study this sample seismogram and be sure you can identify these parts:
• P-waves and the P-wave arrival time
• S-waves and the S-wave arrival time
• S-P interval (expressed in seconds)
• S-wave maximum amplitude (measured in mm)
Figure 1
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Locating the Epicenter: When an earthquake occurs, the energy travels through and across the
Earth’s surface in the form of seismic waves. Using the difference in the arrival time of the Pwave and the S-wave at seismic stations we can find the epicenter of an earthquake using a
triangulation process.
Step 1: Find the time it took between the beginning of the P-wave and the beginning of the Swave for each of the stations listed in Table 1 from the seismograms below. Determine the S-P
time interval for the 3 different stations and record in Table 1.
Seismic
Station
Eureka, CA
S-P Interval
(s)
Table 1: Earthquake 1
Dist. to Epicenter
Max Amplitude of S-wave
(km)
(mm)
Elko, NV
Las Vegas, NV
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Step 2: Use the S-P graph below and the estimates you made for the S-P time intervals from the
three seismograms to calculate distance to epicenter in km and record in Table 1. The horizontal
grid is in one second intervals.
S-P Graph
Step 3: Triangulation of the Epicenter. To find the epicenter, you must use the distance from at
least three different stations. To do this, set a compass at a radius equal to the distance from the
epicenter y using the scale at the bottom of Map 1. Use your compass to then draw a circle,
centered on that station. Do this for all three stations. When you have completed the circles for
all stations, find the location where those three circles intersect or are closest to meeting. This is
the epicenter.
What city is the epicenter closest to? _____________________________
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Map 1
Earthquake Magnitude: The magnitude of an earthquake is a measurement of strength taken
using the seismogram. The scale, known as the Richter Magnitude Scale, was introduced into the
science of seismology in 1935 by Dr. C.F. Richter of the California Institute of Technology in
Pasadena. The magnitude of an earthquake is an estimate of the total amount of energy released
during fault rupture. The Richter magnitude of an earthquake is a number: about 3 for
earthquakes that are strong enough for people to feel and about 8 for the Earth’s strongest
earthquakes. Although the Richter scale has no upper nor lower limits, earthquakes greater than 9
in Richter magnitude are unlikely. The most sensitive seismographs can record nearby
earthquakes with magnitude of about -2 which is the equivalent of stamping your foot on the
floor.
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The Maximum Amplitude of the S-wave, measured form the base to the maximum height of the
wave is related to earthquake Magnitude as seen in Figure 2. The horizontal grid lines are spaced
at 10 millimeter intervals. In this example the maximum amplitude is about 185 mm.
Figure 2
Step 4: Measure the Maximum Amplitude of the S-wave in millimeters for each of the 3 stations
and record in Table 1.
The Richter Nomogram: The relationship between Richter magnitude, the maximum amplitude
of the S-wave and S-P interval is complex. A graphical device (a nomogram) can be used to
simplify the relationship and estimate magnitude using distance and amplitude. The Richter
Nomogram below shows a dotted line that represents the “standard” Richter earthquake. This
standard earthquake is 100 km away and produces 1 mm of amplitude on the seismogram. It is
assigned a magnitude of 3. Other earthquakes can then be referenced to this standard. Note that a
100 km distance earthquake of magnitude 4 would produce 10 mm of amplitude and a magnitude
5 would produce 100 mm of amplitude. Thus 1, 10 and 100 are all powers of 10 and so the
Richter Scale is said to be exponential. A change of one unit in magnitude (say from 4 to 5)
increases the maximum amplitude by a factor of 10.
Step 5: Determine the magnitude of the earthquake for each station using a ruler to draw a line
from each amplitude (on the right) on the nomogram to the corresponding distance (on the left).
Find the point at which they all intersect or the closest point. This is the approximate magnitude.
(Note: Use The Richter Nomogram to approximate the magnitude of each earthquake.)
The approximate magnitude of this earthquake was _________________
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The Richter Nomogram
Using the steps above, fill in Table 2 to determine the epicenter of the following earthquake as
well as the magnitude.
Seismic
Station
Fresno, CA
S-P Interval
(s)
Table 2: Earthquake 2
Dist. to Epicenter
Max Amplitude of S-wave
(km)
(mm)
Las Vegas, NV
Phoenix, AZ
What city is the epicenter closest to? _____________________________
The approximate magnitude of this earthquake was _________________
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Using the steps above, fill in Table 3 to determine the epicenter of the following earthquake as
well as the magnitude.
Seismic
Station
Pusan
S-P Interval
(s)
Table 3: Earthquake 3
Dist. to Epicenter
Max Amplitude of S-wave
(km)
(mm)
Tokyo
Akita
What city is the epicenter closest to? _____________________________
The approximate magnitude of this earthquake was _________________
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Map 2
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The Richter Nomogram
Using the steps above, fill in Table 4 to determine the epicenter of the following earthquake as
well as the magnitude.
Seismic
Station
Chichuahua
S-P Interval
(s)
Table 4: Earthquake 4
Dist. to Epicenter
Max Amplitude of S-wave
(km)
(mm)
Mazatlan
Rosarito
What city is the epicenter closest to? _____________________________
The approximate magnitude of this earthquake was _________________
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Map 3
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Instructions: Go to https://earthquake.usgs.gov/earthquakes/map/ and find the largest
earthquake that happened in the world today and answer the following questions.
1. Where did this earthquake occur, closest city and epicenter?
2. What was the magnitude of this earthquake?
3. How deep was the hypocenter?
4. What time did this earthquake occur?
5. Open Google Earth or Google Maps. Get as close as you can to the epicenter. What do you
think caused this earthquake?
6. How many seismic stations are necessary to locate the epicenter of an earthquake?
7. What is the process called of using these stations to pinpoint the epicenter?
8. What types of seismic waves arrive first? Why is that?
9. What type of materials can P-waves travel through?
10. What type of materials can S-waves travel through?
11. What did the information from questions 9 and 10 teach us about the interior of the Earth?
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