|Department of Earth & Atmospheric Sciences|
Saint Louis University
Quizzes & Exams
All previous essays are fair game!
Additional Potential Essays for Final Exam
|Discuss some aspect of earthquakes (you choose the topic). Examples: Quantifying earthquake size; Earthquakes and tsunamis; Earthquake Sequences, Earthquakes and faults; Earthquake effects on the landscape; Earthquake effects on buildings, etc..|
|Discuss earthquake size and magnitude. Describe several different magnitude scales and how they relate to the wave-types and periods used to make a magnitude measurement. Don't forget magnitude saturation and the relationship of an earthquake size to physical properties of the rupture such as slip and area.|
|List and describe the three types of plate boundaries and discuss the main geologic features such as earthquake activity (number of events, depth of events, etc.), volcanoes (where are volcanoes located relative to plate boundary, what type of volcanism is associated with boundaries, etc.), what type of faulting, bathymetric and topographic expressions, etc.. (This question is very similar to a question from November 15 - I've added faulting)|
|Describe the earthquake "cycle", the elastic rebound model (it's strengths and weaknesses), and how the Elastic rebound model stands up to our observations.|
Quiz #5 Potential Essay Questions (November 15)
|Describe the contributions of studies of Earth's magnetic field to the development of plate tectonics.|
|List and describe the three types of plate boundaries and discuss the main geologic features such as earthquake activity (number of events, depth of events, etc.), volcanoes (where are volcanoes located relative to plate boundary, what type of volcanism is associated with boundaries, etc.), bathymetric and topographic expressions, etc.|
|Plate tectonics is a comprehensive explanation for the way the outer part of the planet works. Describe several of the main geologic features that are well explained by the plates.|
Quiz #4 Potential Essay Questions (November 3)
|Describe the variation in P-wave velocity throughout the Earth. Don't think in terms of the wave traveling, but study the plot of P-velocity versus depth and describe the physical changes that are associated with the major features in that curve.|
|Use a simple mechanical analog to illustrate the basic ideas behind a seismic recording system.|
|What are the four basic seismic wave types, and what distinguishes them from one another?|
|Describe the wave propagation phenomena (reflection, refraction, dispersion) and how they add complexity to seismograms.|
For Mid-Term Potential Essay Questions (October 13)
Outline the origin and abundance of the elements and include a discussion of the role in nuclear fusion and fission in the processes that produced the Universe (feel free to use cartoons to illustrate your answer). Describe the information contained in meteorites and what the observations tell us about the solar system and planets. Sketch a cartoon of Earth that illustrates the main compositional "zones" of the planet and the major chemical components in each. Then indicate which of these zones is hot, cool, convecting, etc. Imagine that you are trying to explain the size and age of the Universe to a friend. Develop simple analogies that place the immensity of the universe and the depth of time in a perspective. Don't worry about many details, but make the point.
Quiz #3 Potential Essay Questions (October 4)
Describe and discuss the scientific problem-solving method. Give a thorough example of using the same ideas to solve a common nonscientific problem (for example, supposed your "Walkman" stopped working, how would you determine what was wrong?). Given a sequence of items such as playing cards or other objects, compose a set of hypotheses to explain the "pattern" in the sequence. For each hypothesis, clearly identify the predictions for the next item and which additional items would support or nullify the hypothesis. List the basic groupings of fallible or "bad" arguments and provide at least one specific example from each category. What are the practices common in sound critical thinking? Why is it likely that unlikely things should happen?
Quiz #2 Potential Essay Questions (September 27)
What are some things you should do before an earthquake? What should you do during an earthquake if you are in a vehicle, in a building, or outside? Describe the intensity of shaking produced by earthquakes, how we measure it, and the factors that can influence the shaking intensity level. Be prepared to intelligently discuss the selection of a site for a "critical structure" (power plant, hospital, highway, etc.) given a map delineating the near-surface rock and soil distribution and earthquake or fault locations. Describe the seismicity of the United States (compare the levels of activity in different regions). Discuss the impact of earthquakes on human societies. How could an accurate earthquake prediction method help us deal with earthquakes? What could it not change? What would be the problems associated with a prediction scheme accurate only 60% of the time?
Quiz #1 Potential Essay Questions (September 13)
What are the steps to writing a good essay question answer (on an exam)?
Sample Exam Questions from Fall 1997
More Sample Exam Questions from Fall '97
Shake, rattle, and roll! In this short article, we answer common earthquake questions and answers to give you a basic understanding of this disruptive event.
What is an earthquake?
An earthquake is the movement of the Earth’s crust caused by pieces of the crust suddenly shifting at faults, or cracks in the Earth.
What determines that an earthquake is really an aftershock?
Aftershocks are earthquakes. Aftershocks do not have a precise definition, but are less intense than a mainshock (generally, the event with the largest magnitude) and occur in the same area. Any subsequent earthquake in the same area, but with less magnitude, is considered an aftershock, until activity in that area returns to normal. Aftershocks are generally caused by the “readjustment” of Earth’s crust in response to a larger earthquake and occur even after very small earthquakes.
Where was the largest-magnitude earthquake in the 50 states, and when was it?
The strongest recorded earthquake in the United States was near Prince William Sound, Alaska, on March 27, 1964. It measured a 8.4 on the Richter scale and killed 131 people. It also caused a 50-foot tsunami that traveled 8,445 miles at 450 miles per hour. This earthquake’s tremors were felt in California, Hawaii, and Japan.
However, the New Madrid (Missouri) Earthquake, which was not recorded, is considered by many to have been the most severe in U.S. history. This series of earthquakes started in December 1811 and lasted until March 1812. It shook more than two-thirds of the United States and was felt in Canada. It changed the level of the land by as much as 20 feet, altered the course of the Mississippi River, and created new lakes west of Mississippi and Tennessee. Because the area was so sparsely populated, there was no known loss of life.
How often do severe earthquakes occur on the West Coast?
The states of California and Nevada experience the most earthquakes. More than 300,000 earthquakes have been recorded in these two states since 1836, including 10 of the 15 largest earthquakes in the contiguous United States.
The largest earthquake in California, and the second largest in the United States, registered 7.9 on the Richter scale and occurred along the San Andreas Fault in Fort Tejon in 1857. One person was killed, and the earthquake caused significant property damage.
Here are some more recent examples of severe earthquakes in that area:
- A 1933 quake in Long Beach, California, registered 6.3, killed 115 people, and caused $40 million in damage.
- A 1952 quake in Kern County registered 6.1, killed 12 people, and caused $60 million in damage.
- The famous Loma Prieta quake of 1989—watched by many during the World Series—registered 7.1, killed 63 people, injured more than 3,700, and caused $6 billion in damage.
- The Northridge quake of 1994, which happened in a densely populated area of Los Angeles, registered 6.8, killed 57 people, seriously injured more than 1,500, and resulted in $20 billion in damage, including several important Los Angeles freeways. For many days after the earthquake, thousands of homes were without gas and electricity, and 49,000 homes had no water, making this one of the biggest earthquakes in terms of disruption of life.
What have been the most recent earthquakes and where were they?
In April 2009, one earthquake struck central Italy, registering a 6.3. The next day, a 4.9–magnitude aftershock hit the same area.
So far, in 2010, there have been six recent earthquakes.
Four were in January: a 6.5–magnitude quake off the shore of Northern California, 4.3–magnitude quake in Southern California, a 7.0–magnitude quake approximately 16 miles from Haiti’s capital city of Port-au-Prince, and a 6.1–magnitude aftershock again in Haiti.
One was in February in central Chile; it registered an 8.8.
One other quake was in April; it registered a 7.2 and struck just south of the U.S. border near Mexicali.
Where does the seismograph come from?
The American scientist John Winthrop (1714-1779) was one of the first to make scientific studies of earthquakes and is known as the founder of seismology. However, we cannot say that he was the inventor of the seismograph, as it is quite likely that various versions of this “machine” had already been constructed by his time.
We do know that Zhang Heng invented an earthquake detector in China around A.D. 132. It consisted of a copper-domed urn with dragons’ heads—each containing a bronze ball—around the outside. Inside the dome was a pendulum that would swing when the earth shook and knock a ball from the mouth of a dragon into the mouth of a bronze toad waiting below. The ball made a loud noise and signaled the occurrence of an earthquake.