Geology 105 (Fall 2007) Instructor: Robert J. Varga Teaching Associate:

In addition to the assigned reading, you are asked to answer several "Preparation Questions" and bring these to class. Often these questions will related directly to the reading. At times you will be directed to the WEB to answer questions. These questions will be handed out to you during the class prior to the class at which they are due to be finished. The questions will also be posted on our website so that you should always have access to them. During the class the questions are due, I will normally call on students to give their answers. Occasionally I will ask for all the papers of a particular day to be turned in at the beginning of class to be graded as quizzes. Feel free to use any sources of information, though, including other books, articles, handouts or the Web. This page will serve arunning collection of preparation questions throughout the semester with the most current questions at the bottom (scroll down).

These questions will be passed out in class (in addition to being on line) the class before they are due. You are responsible for bringing your written answers with you to class. Again, I may ask for them to be turned in as the equivalent to a Quiz.

Week 1

For August 27

1. What defines an Earth "hazard"?
2. If natural Earth phenomena (e.g. earthquakes, volcanic eruptions) occur at about the same rate over time, why have risk and loss (both in terms of life and property) increased dramatically across the globe?
3. We will talk about hazard "mitigation" thoughout the class. What is "mitigation" in regards to Geologic Hazards?

For August 29

1. What is density?
2. How does density change as we go into the Earth from the crust, through the mantle, into the core?
3. What do these density changes primarily reflect?
4. What is the "Moho"?

Week 2

For September 3

1. How is the current theory of Plate Tectonics different from the older theory of Continental Drift?
2. What are the three fundamental types of plate boundaries?
3. What type of plate boundary is.......

a. western California_____________________________________

b. East Africa__________________________________________

c. Pacific Northwest_____________________________________

For September 5

What do Iceland, Hawaii and Easter Island have in common?

What is the role of transform faults in plate tectonics?

What kind of plate boundary was the 1964 Alaskan Earthquake related to? (See the "Hazard Web Links" page of our course website to help answer this?

For September 7

What geologic structures produce earthquakes?

What does a seismograph record?

One of the most important concepts for trying to forecast future earthquakes is the concept of the seismic gap. What is this?

Week 3

For September 10

During lectures on earthquakes as well as other hazards, we will often refer to California and its geography. To make this more tangible for you I'd like you to approximately locate and label the following geographic/geologic things on the physiographic map of California that you can download here (PDF of California). Use whatever resources you might find (your text, maps, atlases, online sources, etc.)

The following cities;
Los Angeles
San Diego
San Francisco

The following physiographic features;
Sierra Nevada Mountains
Coast Ranges
"Transverse" Ranges (aka San Gabriel Mountains)
Mount Shasta
Mohave Desert

The following geologic features;
approximate trace of the San Andreas fault
approximate subduction zone boundary offshore of Northern California

For September 12

What was the cause of the most deaths during the Loma Prieta earthquake?

What is the difference in ground motion created experienced by the passage of "p" (compressional) waves versus "s" (shear) waves?

Explain the elastic rebound theory for the origin of earthquakes along faults.

For September 14

1) How thick is the lithosphere (in km)?

2) The Earth interior primarily cools by;
a. Conduction
b. Convection
c. Reconciliation
d. Deduction
e. Radiation

3) Match the fault type to the probable tectonic environment (e.g. place a letter corresponding to a fault type next to the appropriate plate margin type).

4) State whether an increase in the following parameters makes rocks more or less brittle (e.g., prone to fracture and production of earthquakes).

a. increase in temperature_______________________________

b. increase in pore fluid pressure__________________________

c. increase in Earth's, or confining, pressure__________________________

d. increase in depth____________________________________

5) Rocks at Convergent Margins produce larger earthquakes because.....

a. they are occur in volcanic areas.

b. they are under intense pressure

c. the rocks have high fracture strengths

d. the rocks break easily under extension

e. none of the above

Week 4

For September 17

1) We often talk about "the San Andreas fault". How is the transform plate boundary in California more complicated than that?

For September 19

1) What are "blind thrusts" and why would they be particularly dangerous in the Los Angeles area?

2) What is the significance of the Ft. Tejon earthquake along the San Andreas fault?

3) What is the difference in both amplitude of shaking and energy release between Richter magnitude 5 and magnitude 6 earthquake?

For September 21

1) How does the pattern of earthquakes along the Anatolian fault in Turkey relate to the so-called "seismic gap" theory?

2) Why did the M6.8 Nisqually earthquake near Seattle in 2001 cause only minor damage?

3) What is the local magnitude of an earthquake with a maximum amplitude of shaking on a seismogram of 28.5 cm?

Week 5

For September 24

1) Define briefly the term "intraplate earthquake".

2) Peruse the OhioSeis seismic network web pages (look at your syllabus). How many stations are currently in the network?

3) What is the value in having such a dense network of seismometers in Ohio?

4) Again, perusing the web sites for both the OhioSeis seismic network and The College of Wooster Seismic Station, determine where in the state the most recent (within the last 10-15 yrs) outbreak of earthquakes has been.

For September 26

1) Describe the difference between an earthquake forecast and a prediction.

2) What are some issues that you might imagine government officials should , or would, consider prior to issuing an earthquake prediction in a highly populated region such as L.A.?

For September 28

Exam Date; see Study Guide for Exam #1

Week 6

For October1

no questions but do reading!

For October 3

1) What is the name for the type of eruption that occurred at Mt. St. Helens?

2) Draw the "silica tetrahedron" and label the elements that form it.

3) What is viscosity?

4) The three main volcanic rock compositions are andesite, basalt, and rhyolite. Order these three rock types in terms of increasing;

a. silica content:

b. gas content:

c. viscosity:

d. explosivity of eruption:

For October 5

1) What are the different types of silicate structures?

2) Place the different types of silicate structures in order of increasing silica content and in order of decreasing melting temperature.

3) Explain "partial melting" of a rock and its affect on the silica content of the resulting magma relative to the parent rock.

Week 7

For October 8

1) What kind of volcanoes make up the Hawaiian islands?

2) Where do eruptions tend to occur on large shield volcanoes, such as Kilauea?

3) How do stratovolcanoes differ from shield volcanoes in terms of dimensions and types?

For October10

1) What is a "Plinian" eruption?

2) How and why do calderas form?

For October12

1) What might be the origin of Plato's story of the lost city of Atlantis?

2) What are some "precursor" events to volcanic eruptions?

3) What is the most dangerous volcanic area in southern Italy? Is it Mt. Vesuvius?

Week 8

no prep questions: Fall Break

Week 9

For October 22

1) What is the "angle of repose" in sediments? How does this relate to landslides?

2) How does the "toe" of a landslide differ than the "head" area of a landslide?

3) Where does water exist in sedimentary rocks?

For October 26

1) What are the differences between a "rock fall", a "rock avalanche" and a "landslide"?

2) Speculate on some of the future geologic hazards that might become a problem as the result of the current wildfires in southern California

Week 10

For October 29

1) Write the formula for Resistance (R) to sliding of a rock mass down a slope as discussed in class. Define all of the variables.

2) Discuss three factors that vegetation affects that help prevent landslides from occuring.

3) Describe a hypothetical area that has the worst possible conditions for landsliding.

For November 2

1) List the at least four ways in which humans can contribute directly to the landsliding.

2) List four ways that humans can potentially decrease the potential for landsliding in an area.

Week 11

For November 5

Week 12

For November 12

1) How does discharge affect the capacity of a stream or river?

2) How do point bars and river meanders migrate?

3) If you live in a 100 year floodplain and experience a flood this year, when might you expect the next flood?

4) What is river avulsion and how does it occur?

For November 12

1) How is the Atchafalaya River-Mississippi River "problem" similar to the problems along the lower reaches of the Yellow River in China?

For November 14

1) How is the porosity of a sediment different from its permeability? Use any source available to answer this question.

2) Why is land subsidence permanent?

3) How does groundwater (which we drink) make caves?

Week 14
For November 30

1) Describe with a simple drawing how longshore drift works and how it affects sand movement along coastlines.

2) What is beach replenishment and why is it a doomed solution to beach erosion?

3) Why do some scientists believe that we are moving into an era of larger and more frequent hurricanes (use any source, including the web).