Physical
Geology
R. Lopez
1)
Define
both stress and strain. What is strain
energy?
2)
About
how much faster is a P-wave than an S-wave?
About how much slower are the surface waves from the S-wave?
3)
Strain
is the result of what kind of changes in a rock?
4)
What
are the three types of stresses? What tectonic boundary is related to
each? Sketch all three showing arrows
of deforming stress.
5)
What
are the links between deformation, energy, and earthquakes?
6)
How
are earthquakes and faults related?
7)
Describe
the elastic rebound theory.
8)
Describe
and sketch the relationship between the focus, epicenter, and surface rupture
for a dipping fault plane.
9)
Where
do deep focus earthquakes occur, what is the maximum depth to their focus, and
what controls this limit? (Why is there
a Benioff Zone?)
10)
What
are typical focal depths of California earthquakes?
11)
What
is the relationship between rock types (hard vs. soft and consolidated vs.
unconsolidated) and ground shaking.
12)
How
do seismographs work?
13)
Define
seismograph, seismogram, epicenter, focus, p-wave, s-wave, Love wave, Rayleigh
wave, surface waves, body waves, amplitude, logarithm, s-p interval,
unconsolidated, magnitude, and intensity.
14)
Sketch
a simple seismograph depiction horizontal movement.
15)
How
are active faults officially defined? What is the Alquist-Priolo Law?
16)
What
are the differences among P, S, and surface waves?
17)
What
is the evidence that the outer core is liquid?
18)
Sketch
a simple seismogram tracing showing the P, S and surface waves.
19)
Discuss
how the epicenter of an earthquake can be located? Be able to do this on an exam.
Know how to calculate p-wave and s-wave arrival times off of a
seismogram. Know how to calculate
distance to epicenter using the (s-p) vs distance curves.
20)
What
specifically controls the Richter magnitude?
Be able to compare the amplitudes of seismic waves yielding different
Richter magnitudes (e.g., compare amplitudes of magnitude 4 and 6 quakes).
21)
What
is the principal problem with the Richter magnitude? (“The Richter magnitude does not directly measure the overall
mechanical power of the seismic source, just as the strongest wind gust is not
a reliable measure of the overall force of a wind storm.” Bolt, 1993, p. 59).
22)
What
is MW, why is it “better” than the Richter magnitude, and what three
factors are considered in its calculation?
23)
What
is MO? Calculate the Mw of
an earthquake with 5.5 meters of slip over a 300 km x 2 km area with rock
having an elastic modulus of 8.2 x 1010 N/m2
24)
How
does “earthquake intensity” differ from magnitude, how is it measured, and what
factors influence it?
25)
What
is the San Andreas Fault System? On a
map, be able to identify the San Francisco Bay Area faults discussed in
lecture.
26)
What
is creep and how does if differ from a long-term slip rate?
27)
Name
two nearby faults that creep.
28)
What
is a seismic gap, and what is the seismic gap theory?
29)
Which
is the most dangerous fault in the San Francisco Bay Area?
30)
Why
is the fault referred to in question above considered to be the most dangerous?
31)
Using
seismic gap theory, where will the next earthquake occur along the San Andreas
Fault in the San Francisco Bay area?
32)
Compare
and contrast the amount of slip (displacement) that occurred during the 1906
S.F. quake and the 1989 Loma Prieta quake.
33)
What
was the time of shaking for each of these quakes mentioned above?
34)
A
seismograph records the p-wave arrival time at 1:00pm and 30 seconds. The s-waves arrives at 1:02pm and 15
seconds. What is the (s-p) interval? What time did the earthquake rupture?