GEOLOGY 1419

PHYSICAL GEOLOGY

FALL 2009

 

 

Required Text:     EXPLORING  GEOLOGY: by Reynolds et al, McGraw-Hill, 2008.

 

Instructor:             Dr. Gerry Clarkson

W-106

Phone:   (325) 646-2502 ext. 5407                  E-mail:   gclarkson@hputx.edu

 

Lecture:                 MWF 11:00-11:50 AM in W-107

Lab:                       M 2:00-4:00 PM in W-107

 

Office Hours:       Office hours will be posted on my office door.  A tentative list of office hours for this semester is

 

M            9:00-10:00 AM, 4:00-5:00 PM        Th           8:30-9:30 AM

                                                T             8:30-9:30 AM                                      F              9:00-10:00 AM, 1:00-2:00 PM

                                                W            9:00-10:00 AM

 

I will be available immediately after class if you wish to talk to me briefly on an individual basis.  If you wish to talk to me at some time other than office hours, please feel free to talk to me about an appointment for another time.

 

 

COURSE DESCRIPTION

 

Content and Objectives

 

Physical Geology (GEO 1419) satisfies 4 hours of the general education natural science with a laboratory requirement.  In general this course should help you in developing scientific literacy through an appreciation of the contributions of science to modern life, development of awareness and measures necessary for ecological responsibility, and development of a background of information.  This course is designed to survey the basic areas of physical geology.  There will be a brief introduction to historical geology as well, since the two subjects are closely related.  We will discuss rocks and minerals; Earth's structure, internal processes and surficial processes; and plate tectonics.  From this course you should obtain a basic understanding of the materials which form our Earth and the processes which shape our Earth.  You should also gain an appreciation of how geology relates to daily life in such diverse ways as resource availability, natural hazards and environmental issues.  Such information will make you a better informed citizen on many issues of our day.  Students will be assessed by tests, laboratory exercises, a paper or thought question assignments and class participation. 

 

Prerequisites

 

There are no prerequisites for this course, however high school level math and reading ability are expected.

 

Format

 

The lecture and lab will be integrated for this class.  We will discuss text material and related lab material together.  Therefore, you will want to bring your text and appropriate lab materials to all class meetings.

 

 

 

 

 

 

ASSIGNED READING AND CLASS SCHEDULE

 

Assigned Reading

 

Please read any assigned material before class.  This will give you the needed background for each class and will enable us to use class time to answer questions, discuss the material and concentrate on the more difficult material.  Our discussions and activities will assume that you have read the appropriate material. You are responsible for all assigned reading whether it is discussed in class or not.  Remember to check the lab exercises for any materials (colored pencils, rulers, etc.) which you will need to bring.

 

I plan to have tests at the following intervals

 

                                Test 1     after Chapters 1-4

                                Test 2     after Chapters 5-9

                                Test 3     after Chapters 10-14

                                Test 4     after Chapters 15-19

                                Final       comprehensive

 

The final will be given at its scheduled time during the final exam period (Wednesday, December 16 from 10:30 AM-12:30 PM).  Please note that this schedule is tentative and may be altered, including the number of tests to be given.

 

GRADING

 

Course grades will be based on tests, lab exercises, a research paper and a comprehensive final.  These components will be weighted as follows: tests-50%, lab exercises-20%, thought questions-15%, final-15%.

 

Tests

 

The tests will cover material discussed in class and material from text reading assignments.  Tests will be approximately 50 minutes in length.  They will consist of multiple choice and essay questions.

 

Lab Exercises

 

Assigned material should be read before class so that you are ready to do the exercises in class.  Remember to bring any required supplies such as pencils, rulers and so forth with you to lab.  Lab exercises will be due at a time indicated in class.  Late labs may be subjected to a penalty.

 

Students are expected to conduct themselves in a safe manner at all times in the laboratory.  There should be no horseplay or unauthorized experiments performed.  Any questions concerning safety should be answered before continuing with an exercise.

 

Thought Questions

 

You are to choose 5 of the “Questions for Further Thought”, found in the handout, and discuss them. Guidelines for these discussions will be found below.  You may turn in your discussions throughout the semester, but AT LEAST 1 of them is due by mid-term (Wednesday, October 14) and the remainder are due NO LATER than the last regular class day (Wednesday, December 9).

 

 

 

Final Exam

 

The final exam will be comprehensive as well as including specifically any material covered since the last class test.  The final will be on Wednesday, December 16, from 10:30 AM-12:30 PM. 

 

Extra Credit

 

Class participation: Up to 2 percentage points of extra credit may be awarded for class participation.

 

Articles:  One percentage point of extra credit may be earned by preparing a brief (about 1 page) summary of an article from a current newspaper or magazine which relates to material we are discussing in class.  Along with the written summary you should be prepared to briefly describe the article to the class so we may discuss it.  Please indicate to me at the beginning of the class when you wish to present an article.  Once a particular article has been presented in class it is no longer eligible for presentation.  You may present two articles during the semester (for a possible 2 percentage points total of extra credit); however only one summary per student per week is permitted.

 

Attendance

 

Howard Payne attendance policy states that a student cannot receive a passing grade in a course unless they have attended at least 75% of the scheduled classes.  Failure to attend 75% of scheduled classes will result in a failing grade.

 

Cheating

 

The first incident of copying, plagiarism, or other form of academic dishonesty will result in a score of 0 for that particular part of the assignment.  The second incident will result in a score of 0 for the entire assignment.  The third incident will result in a grade of F for the course.

 

Assignment of Grades

 

It is my intention to assign grades according to the following scale.

 

                                          90-100%   A                               60-70%    D

                                          80-90%      B                               0-60%      F

                                          70-80%      C

 

The scale for final grades may be adjusted slightly downward, but do not count on that.

 

 

BIBLIOGRAPHY

 

I have a variety of introductory books on physical, historical and environmental geology which can be made available to you.  These books contain general information and additional bibliographic references. 

 

Journals in the library which will have articles relating to subjects discussed in this class are American Scientist, Scientific American, National Geographic, Journal of Geology, Nature, and Science.  I also have the journal Geotimes, which I can make available.

 

Some Internet resources are listed on a separate page.

 

SUGGESTIONS

 

Some suggestions on how to approach this course.

 

1.  Attend class and lab.  For most students regular, active attendance is an extremely important key to mastering the material.

 

2.  Read the assigned material before class.  This will allow you to better appreciate class discussion, ask questions and contribute your insights to the rest of the class.

 

3.  Think of class as an active exercise on your part.  Ask questions about things you do not understand from the reading or from previous discussions.  Asking questions will not only benefit you, but it will likely benefit others in the class and will also benefit me in that I will not have to guess at what I should be trying to explain better.  Also feel free to raise questions on topics of interest to you, even if they are not directly mentioned in the reading or class discussion.

 

4.  If you would like to discuss something in more detail than time permits in class, please feel free to see me on an individual basis.

 

 

INTERNET RESOURCES

 

Organizations

 

American Geological Institute                                                  http://www.agiweb.org/

 

Geological Society of America                                                 http://www.geosociety.org/

 

National Aeronautics and Space Administration                  http://hypatia.gsfc.nasa.gov/NASA_homepage.html

 

United States Geological Survey (USGS)                                http://geology.usgs.gov/

 

USGS Water Resources Division                                              http://h2o.usgs.gov/

 

A comprehensive listing of states, U.S. provincial,                http://www.lib.berkeley.edu/EART/surveys.html

And various international geological surveys and

Associations can be found at this site.

 

 

Rocks and Minerals

 

Mineralogical Society of America                                            http://www.minsocam.org/

 

Smithsonian Institution Gem and Mineral Collection          http://nmnhwww.si.edu/minsci/collect.htm

 

Earthquakes, Volcanoes, and Plate Tectonics

 

Canadian National Earthquake Hazards Program                              http://www.seismo.emr.ca/

 

Hawaii Volcanoes Observatory                                                                http://hvo.wr.usgs.gov/

 

National Geophysical Data Center (U.S.)                               http://www.ngdc.noaa.gov/

 

USGS Cascades Volcano Observatory                                   http://vulcan.wr.usgs.gov/home.html

 

USGS information relating to plate tectonics         http://geology.usgs.gov/publications/text/dynamic.html

(with many diagrams)

 

USGS National Earthquake Information Center                  http://wwwneic.cr.usgs.gov/

 

 

Surface Processes  (Streams, Flooding, Glaciers, Landslides, Climate Change, Desertification)

 

Global Change Master Directory                                              http://gcmd.gsfc.nasa.gov

 

INSTAAR Institute for Arctic and Alpine                               http://tintin.colorado.edu/glaciology/

Research (U. of Colorado)

 

Smithsonian National Air and Space Museum                     http://drylands.nasm.edu:1995

Online exhibit on drylands/desertification

 

USGS flood-hazard information                                              http://www.usgs.gov//themes/flood.html

 

USGS National Landslide Information Center      http://www.landslides.usgs.gov/html_files/nlicsun.html

 

USGS real-time stream gaging data                                         http://h2o.usgs.gov/public/realtime.html

 

 

Resources (Water, Mineral, Energy, Soil)

 

Canadian Soil Information System                                         http://res.agr.ca/PUB/CANSIS/_overview.html

 

International Atomic Energy Agency                                      http://www.iaea.or.at/worldatom/

 

National Resources Canada                                                     http://www.NRCan.gc.ca/

 

U.S. Department of Agriculture Natural Resources              http://www.nhq.nrcs.usda.gov/

Conservation Service 

 

U.S. Department of Energy                                                       http://www.em.doe.gov

 

U.S. Energy Information Administration                                                http://www.eia.doe.gov/

 

USGS Energy Resource Surveys Program                              http://energy.usgs.gov/

 

USGS National Water-Use Information Program                 http://h2o.usgs.gov/public/watuse/wufactsheet.html

 

USGS Mineral Resource Surveys Program                             http://minerals.er.usgs.gov/

Guidelines for Questions for Further Thought

 

 

1.       You are to choose to answer 5 of the Questions for Further Thought, which are found in the handout.  Each one of these five questions is to come from a different chapter.  Please indicate the question you are responding to on your paper.

 

2.       The nature of you response will be dictated by the question that you choose.  Some questions may call for you to find and report on information, some may ask you to make reasonable estimates and calculate a quantity, some may ask for an opinion on an issue, and so forth.  In your response you may want to discuss sources of information, evaluate the reasonableness of assumptions and calculated quantities, or consider assumptions on which opinions are based.

 

3.       Your responses to the thought questions should be AT LEAST 500 words (about the equivalent of two normal typewritten pages).  If you cannot give a response to a question that meets the minimum length requirement then you should choose a different question.

 

4.        You should give references for any sources of information you use in responding to the question.

 

5.       The responses will be graded mainly on content.  Remember, however, that a clear, well-written presentation will help convey the content.  If I cannot read and understand your discussion, it is not likely to get a good grade.

 

6.       Your responses are to be submitted in MS-Word format.  You may either send the paper to me as an e-mail attachment or give it to me on some approved storage medium (for example, CD or floppy disk).  It is your responsibility to verify that I have received and can read your paper after you have submitted it.

 

7.       You may turn in your discussions throughout the semester, but AT LEAST 1 of them is due by mid-term (Wednesday, October 14) and the remainder are due NO LATER than the last regular class day (Wednesday, December 9).

 

8.       Various indexes available in the library will help you get started in tracking down information for your topic.  You may find it helpful to look at the bibliographic references in your textbook or from a book or journal article related to your topic.

 

9.       General sources of information include books and journals from the library.  Some materials not in the library may be obtained through interlibrary loan.  Start tracking down your sources early enough to allow time to use this service.  Some examples of journals in the library which may serve as sources include American Scientist, National Geographic, Journal of Geology, Nature, and Science.  In addition, you may find political and social aspects addressed in journals related to those fields. 

 

QUESTIONS FOR FURTHER THOUGHT

(from Montgomery, 1997;  Fundamentals of Geology, 3rd edition)

 

Chapter 1:  Introducing the Earth

 

  1. If the whole 4.5 billion year span of Earth’s history were represented by one 24 hour day, how much time would correspond to (a) the 600 million years of existence of complex organisms with hard shells or skeletons and (b) the half-million years that Homo sapiens has existed?

 

  1. Many geologic processes proceed at rates on the order of 1 centimeter per year (1 inch=2.54 centimeters).  At that rate how long would it take you to travel from home to school or from your room to class?

 

Chapter 2:  Minerals

 

  1. More ancient rocks generally are less widely found and more difficult to interpret than are younger rocks.  Explain why, in the context of the rock cycle.

 

  1. Choose one of the following minerals or mineral groups, and investigate its range of physical properties and its uses:  quartz, calcite, garnet, clay.

 

Chapter 3:  Igneous Rocks and Processes

 

  1. Considering magma viscosity and density, would you expect volcanic rocks more often to be mafic or silicic in composition?  Why?

 

  1. The minerals quartz, albite, and orthoclase (a potassium feldspar) are sometimes called collectively, the “residua system” in the study of igneous rocks.  How do you suppose this name arose?

 

Chapter 4:  Volcanoes

 

  1. Look up the projections, made prior to the May 1980 eruption of Mount St. Helens or the 1991 eruptions of Mount Pinatubo, of the areas that might be affected by these eruptions, including secondary effects such as mudflows.  Compare the actual consequences with the predictions.

 

  1. Find out if there is any history of volcanic eruptions in your area (a) in historic times or (b) within the last one to two million years.  If so, what was the nature of the activity?  What is the explanation for it?  Might future activity be expected?

 

Chapter 5:  Weathering and Soil

 

  1. Given the reactions in table 5.1 (“Some Chemical Weathering Reactions”), suggest why underground caverns form in limestone but not in granite, even if the granite, even if the granite is weathered.

 

  1. Rates of weathering, and the relative resistance of different rock types to weathering, can often be evaluated with more accuracy using stone buildings, monuments, or even gravestones in cemeteries than by examining natural rocks in the field.  Why?  Suggest some possible limitations on the use of such artificial structures to estimate weathering rates.

 

  1. Inspect a local construction site or farmland, and look for evidence of soil erosion.  Consider what might be done to reduce any problems you identify.

 

 

 

 

 

 

 

 

Chapter 6:  Sediment and Sedimentary Rocks

 

  1. Many organisms that we now know only as fossils lived over a limited span of geologic time.  Consider how this fact might be used to recognize different facies of the same rock unit in an area in which the rocks are generally not well or continuously exposed.

 

  1. In which of the following sediments might you hope to find dinosaur footprints:  (a) a coarse sandstone with pronounced crossbeds; (b) a mudstone with symmetric ripple marks; (c) an oolitic limestone?  Explain.

 

  1. Much of North America is covered by sedimentary rock, miles thick.  Where might such an immense volume of sediment have come from?

 

Chapter 7:  Metamorphism and Metamorphic Rocks

 

  1. Many reactions are so slow at near-surface temperatures that minerals unstable at those temperatures can nevertheless be preserved.  Why does this allow geologists to gather much more information than they could if all mineral assemblages constantly adjusted to new pressure, temperature, or other conditions?

 

  1. Sometimes, during cooling from peak metamorphic temperatures, rocks undergo retrograde reactions, in which lower-grade minerals form again from higher-grade ones.  Considering some of the metamorphic reaction in table 7.1 (“Common Types of Metamorphic Reactions”), how important would you expect fluids to be in retrograde metamorphism?  Explain.

 

Chapter 8:  Geologic Time

 

  1. As noted in the chapter, the best index fossils are those that are found widely distributed over the Earth and derived from organisms that existed only for geologically short periods of time.  Consider why these two criteria are important.  What sorts of organisms might satisfy the first criterion especially well?

 

  1. Each of the various radioactive isotopes has a distinct and unique half-life.  What would be the impact on radiometric dating if all radioisotopes had the same half-life?  If there were only one naturally occurring radioisotope?

 

  1. 3.  The equation for decay of a radioactive isotope is   N=Noe-at   where No is the initial number of parent atoms, N is the number remaining after time t, and a the decay constant characteristic of that parent isotope (proportional to the rate at which it decays).  If each parent atom decays to one daughter atom D, and there is no D present in the sample initially, then after time t, the number of atoms of daughter D present is given by    D= No-N=N(eat-1).  Suppose that you have analyzed a zircon sample in which the ratio of lead-206 atoms to (parent) uranium-238 atoms is 4094:5280.  The decay constant a for uranium-238 is 1.55x10-10 per year. What is the age of the zircon?

 

Chapter 9:  Plate Tectonics

 

  1. It has been proposed (not by geologists) that the phenomenon of apparent polar wander can be explained by a flipping or rotation of Earth’s whole lithosphere as a single unit, rather than by plate tectonics and independent movements of different continents.  Can you suggest any evidence that is inconsistent with that proposal?

 

  1. The Moon, though smaller than the Earth, has a much thicker lithosphere:  The Moon’s radius is only 1740 kilometers, yet its lithosphere is about 1000 kilometers thick.  Would you expect plate-tectonic activity and subduction to occur on the Moon as they do on Earth?  Why or why not?

 

 

 

 

 

 

 

 

Chapter 10:  Earthquakes, Seismic Waves, and the Earth’s Interior

 

  1. Investigate the history of any modern seismic activity in your area.  What is the geologic explanation for this activity, and how probable is significant future activity?  (You might consult the U.S. Geological Survey or state geological surveys for information.)  If a significant hazard is perceived, what plans are in place to respond to it?

 

  1. Research one or more past earthquake predictions made in the United States or elsewhere.  How specific were the predictions?  How accurate?  What was the public response, if any?

 

  1. If you live near a major urban area, collect data on the population in the city on a workday and the rate at which commuters can be moved into or out of the city during rush hour.  Speculate on the implications of your findings for the impact of short-term earthquake predictions.

 

  1. The relatively high cosmic abundance of iron suggests that iron is the dense element that forms the Earth’s core.  In the absence of that constraint, consider whether one could demonstrate in some other way that the core is not made of another metal, such as gold or lead, and if so, how.

 

Chapter 11:  The Continental Crust

 

  1. The identification of suspect terranes is difficult, as demonstrated by their relatively recent recognition.  Suppose that you have found a batholith adjacent to a sequence of interlayered sedimentary and volcanic rocks.  What features or properties might you look for to decide whether or not these are two distinct terranes, formed as different continental blocks that have become juxtaposed?

 

  1. In general, would you expect shield regions to be more or less likely to be in isostatic equilibrium than continental margins?  Why?  Would you expect differences in the extent of isostatic equilibrium between active and passive margins?  Explain.

 

Chapter 12:  The Ocean Basins

 

  1. In what ways might you be able to distinguish a sediment sample from the abyssal plain from a sediment sample collected at the base of the continental slope of a passive margin?

 

  1. Suppose that, while drilling in the sediments on the continental shelf off New England, you find buried fossil coral reefs.  The water there today is too cold for corals.  Suggest at least two possible explanations for the presence of the fossil corals.

 

Chapter 13:  Coastal Zones and Processes

 

  1. Choose any major coastal city, and investigate the extent of flooding that could be expected in the case of eustatic sea-level rise of (a) 1 meter and (b) 5 meters.  For an example of possible problems and responses to them, investigate what is occurring in the city of Venice, Italy, where a combination of tectonic sinking, surface subsidence, and sea-level rise is causing increasing flooding problems.

 

  1. If you live in a near-coastal area, calculate how soon water would reach your home at a rate of sea-level rise of 1 meter per century.

 

 

 

 

 

 

 

 

 

 

 

Chapter 14:  Streams

 

  1. Make a point of visiting a nearby stream.  Walk along the channel, noting meandering, areas where the bank is eroding or point bars are being deposited, and any evidence of human modification of the channel.

 

  1. Investigate the availability of flood-hazard maps for a nearby stream.  How current are the maps and the data upon which they are based?  Have any efforts been made to reduce the flood hazards?  If so, what have they been, what have they cost, and what negative effects, if any, have they had?

 

  1. For a river that has undergone channel modification, investigate the history of flooding before and after that modification, and compare the costs of flood damage to costs of flood-hazard reduction strategies.  (The Army Corps of Engineers engages in many such projects and may be able to supply the information.)

 

Chapter 15:  Ground Water and Water Resources

 

  1. Where does your water come from?  What is the quality at the source?  Is the water treated before consumption?  If the source is ground water, is there evidence that the supply is being depleted?  If so, what plans exist for averting future shortages?

 

  1. If there is a landfill or other waste-disposal site near you, investigate how possible groundwater pollution is monitored.  What tests are made and how often?  If appreciable pollution has been detected in the past, what steps have been taken to reduce or eliminate it?

 

  1. Some activities are commonly cited as water-wasters.  One is letting the tap run wile brushing one’s teeth.  Try plugging the drain, then doing this; then measure the volume of water accumulated during a single tooth-brushing (a measuring cup and a bucket may be helpful).  Consider the implications for water use, bearing in mind that the U.S population is about 265 million, and our strictly biological need of about 1 gallon per person per day.

 

Chapter 16:  Landslides and Mass Wasting

 

  1. What kind of geologic features might you look at to obtain an estimate of the angle of repose of (a) sand and (b) volcanic ash?  What factors might affect the results of your observations or limit their applicability?

 

  1. Spring is landslide season in mountainous areas of many temperate climates.  Suggest at least three reasons for this.

 

Chapter 17:  Wind and Deserts

 

  1. Obvious graded bedding is less common in wind-laid than in water-laid sediments; sorting of wind-deposited sediments is commonly very good.  Suggest explanations for these observations.

 

  1. If you live in a snowy area, make an inspection tour around your home or school buildings after a snowstorm with high winds.  Note the distribution of snow, and try to relate it to the distribution of obstacles to wind flow.  (Readers in sparsely vegetated areas might do the same after a windstorm in dry weather, although the sediment distribution patterns may be more subtle and require closer scrutiny.)

 

Chapter 18:  Ice and Climate

 

  1. How would you distinguish an esker from sediment deposited by a stream not associated with a glacier?  From a natural levee?
  2. Assume that, during the Pleistocene glaciation, one-third of the continental land area was covered by ice.  If the total areal extent of the continents is 149 million square kilometers, that of the oceans is 361 million square kilometers, and sea level was lowered by approximately 130 meters, what was the average thickness of ice over the glaciated areas (ignoring isostatic effects)?  You may also find it interesting to examine a bathymetric (depth) chart of the oceans to see how much new land would have been created by that much lowering of sea level.