GEOLOGY 101
PHYSICAL GEOLOGY
SYLLABUS
INSTRUCTOR:
L.R. GARDNER
Room 206 EWSC
(7-2424)
OFFICE HOURS:
M 10-11 am, T 2-3pm, W 11-12 am
TEXT BOOK:
Tarbuck & Lutgens, EARTH: An Introduction to Physical
Geology, 6 th edition, Prentice-Hall.
LAB MANUAL:
Busch, Laboratory Manual in Physical Geology, 5 th
edition, Prentice-Hall.
GRADING:
1. Your lab TA will give you assignments, quizzes and exams in lab and,
based on your performance, will provide me with an overall numerical lab grade
between 0 and 100 points. Twenty five percent of your lab grade will be based on
a written lab report for a research project that will be described later.
2. There will be a cumulative final lecture exam (multiple choice) during
the finals period in December on which you can earn up to 100 points.
3. There will be 3 to be announced exams (multiple choice) during the
lecture classes, each worth 100 points. I will drop the worst of these three
exams so that you can earn up to 200 points on your two best exams. There will
be no makeups for these three exams so you will get a zero on any that you miss.
4. Your total numerical grade will be the sum of items 1 through 3
so that if you are perfect you will end up with at most 400 points.
a. You will get an A if you have at least 360 points or are in roughly
the uppermost 10 percent of the class. I say "roughly" because I will
look for gaps in the distribution of total scores at which to place boundaries
between letter grades. I will also consider class attendance if you are a
borderline case.
b. You will get a B+ if you have between 340 and 360 points or are
roughly in the next 10 percent of the class.
c. You will get a B if you have between 320 and 340 points or are roughly
in the next 10 percent of the class.
d. You will get a C+ if you have between 300 and 320 points or are
roughly in the next 15 percent of the class.
e. You will get a C if you have between 280 and 300 points or are roughly
in the next 25 percent of the class.
f. You will get a D+ if you have between 260 and 280 points or are
roughly in the next 15 percent of the class.
g. You will get a D if you have between 240 and 260 points or are roughly
in the next 10 percent of the class.
h. You will get an F if you end up with less than 240 points and
are in the last 5 percent of the class.
CLASS ATTENDANCE:
Mandatory!!! If you miss an exam you will get a zero and will
have to rely on your grades in the other quizzes. In other words there will be
no make ups regardless of your excuse. With a class of this size I can not sort
through all of the tales of woe that will inevitably arise. In addition if
you are a borderline case as regards the letter grade criteria outlined above,
attendance may be taken into account in assigning your final grade.
LECTURE SCHEDULE:
Date
Topic
Text Assignment
8-24
Introduction
Ch 1
8-29
Matter and Minerals
Ch 2
8-31
Matter and Minerals
Ch 2
9-5
Igneous Rocks
Ch 3
9-7
Volcanic and Plutonic Activity
Ch 4
9-12
Weathering and Soils
Ch 5
9-14
Weathering and Soil (EXAM)
Ch 1-5
9-19
Sedimentary Rocks
Ch 6
9-21
Metamorphic Rocks
Ch 7
9-26
Geologic Time
Ch 8
9-28
Mass Wasting
Ch 9
10-3
Hydrologic Cycle and Rivers
Ch 10
10-5
Rivers
Ch
10
10-10
Ground Water
Ch 11
10-12
Ground Water (EXAM)
Ch 6-11
10-17
Fall Break, no classes
10-19
Glaciers and Glaciation
Ch 12
10-24
Glaciers and Glaciation
Ch 12
10-26
Deserts and Aeolian Activity
Ch 13
10-31
Shorelines
Ch 14
11-2
Shorelines (EXAM)
Ch 12-14
11-7
Election Day, no classes
11-9
Crustal deformation
Ch 15
11-14
Earthquakes
Ch 16
11-16
Earth's Interior
Ch 17
11-21
Earth's Interior
Ch 17
11-28
Seafloor Spreading
Ch 18
11-30
Plate Tectonics
Ch 19
12-5
Plate Tectonics
Ch 19
12-7
Mountain Building & Continental Evolution
Ch 20
12-11
Final Exam (2 pm)
Ch 1-20
LAB SCHEDULE:
Week
Topic
Aug 28
Minerals
Sept 4
Igneous Rocks
Sept 11
Sedimentary Rocks
Sept 18
Metamorphic Rocks
Sept 25
Rock and Mineral Exam, Topographic Maps
Oct 2
Fluvial Landforms
Oct 9
Glacial Landforms
Oct 16
No Labs
Oct 23
Research Project Data Analysis
Oct 30 Desert,
Shoreline and Karst Features
Nov 6
Folds and Faults
Nov 13
Geologic Maps
Nov 20
Labor Day and Election Day Make Ups for Monday and
Tuesday Labs only
Nov 27
Geophysics
Dec 4
Final Lab Exam
LAB PROJECT:
Geologists and engineers have long been curious about the processes that
govern river drainage networks. When viewed on maps stream networks show a
branching pattern, similar to those exhibited by trees, with trunk streams and
their smaller tributaries. In the 1960s Ronald Shreve hypothesized that stream
networks are "topologically random". Note that he did not say
topographically random. You are going to collect data from maps in the Thomas
Cooper Map Library to test this hypothesis. You and your class mates will pool
your data and then each of you will write a short report describing your results
and conclusions. This exercise will hopefully give you an appreciation of the
scientific method which involves the formulation of a hypothesis, the collection
of data to test the hypothesis, the presentation and analysis of the results,
and the drawing of conclusions from the results. It will also give you a feel
for the use of mathematics and statistics in scientific research.
Now let me define what is meant by topologically random. Here are some
definitions that are illustrated on Figure 1 below. This figure shows an example
of a stream network. Streams that have no tributaries are called external links.
All other links receive drainage from two or more tributaries and are called
internal links. Links are stream segments that connect junctions. The example
network has five external links and four internal links. The total number of
links is nine. In general the total number of links in a network is equal to two
times the number of external links minus one (eg. 2*5-1=9). This rule holds as
long as no more than two tributaries join at a junction.
Shreve defined the link magnitude (LM) of a network as being equal to the
number of external links. The LM of the example network is thus five. Shreve
also defined rules for determining the topological structure of a network. This
is done by taking an imaginary trip through the network. You start at the mouth
of the basin and travel upstream noting whether you are on an internal or
external link. When you get to a junction you must turn left. In your trip you
count each link only once. When you get to the end of an external link you go
back downstream to the first junction that still has links upstream that you
have not yet traveled on. Applying these rules to the network on Figure 1 the
sequence of links on the trip is IIIEEIEEE where "I" stands for an
internal link and "E" stands for an external link. Note again that the
total number links in this sequence is nine. This sequence is called the binary
code for this network.
Figure 2 shows two other networks that also have a link magnitude of
five. Note that they have different binary codes. Thus the networks shown in
Figures 1 and 2 all have the same link magnitude but have different binary
codes. They are thus topologically distinct. It turns out that for networks with
link magnitude equal to five there are 14 topologically
distinct possible networks. If you work at it you might be able to write
out the binary code for each. Shreve hypothesized that in nature each
topologically distinct network for a given link magnitude should have the same
chance of occurring. Thus if we worked out the binary codes for a large number
of link magnitude five networks there should be about 7.1 percent (1/14) of each
topologically distinct type. For basins with a link magnitude of two there is
only one topological possibility (ie. IEE). For link magnitude of three there
are two topological possibilities (try working out their binary codes) so there
should be about fifty percent of each. For link magnitude of four there are five
possible topological varieties (again try working out their binary codes) so
there should be twenty percent of each.
Note that on Figure 1 there are two sub-networks with a link magnitude of
two and one sub-network of link magnitude four. On Figure 2 there are
sub-networks of two, three and four. Thus in general networks with link
magnitudes greater than two have embedded within them sub-networks of lower link
magnitude.
Thus to test Shreve's topological randomness hypothesis you will do the
following.
1. Go to the Thomas Cooper Library which is only open 9-5 weekdays. Bring
several pieces of tracing paper and a ruler with you because they will not allow
you to check out maps.
2. Pick a state at random. Ask the map librarian for the USGS topo index
map for that state. Pick at random a 7.5' quadrangle
map from the index and ask the librarian to get it for you. Find a basin
with a link magnitude of five on the quadrangle. If you can't find a link
magnitude basin on the map, pick another quadrangle. In determining the link
magnitude, only use stream links shown as solid or dashed blue lines on the map.
Reject any network in which more than two tributaries join at a junction.
3. Find and record the latitude and longitude of the mouth of the basin
and the name of the trunk stream if any.
4. Make a tracing of the network.
5. Workout the binary codes of the link magnitude five network and all
link magnitude three and four sub-networks.
6. Make a copy of your work and turn it in to your lab TA on or before
Friday, October 6. If you know what you are doing, this work should not take
more than an hour or so.
Your TA will then compile the data collected by the students in your lab
and combine it with data from all of the other labs. This should give us a
sample size of 100 to 150. The compiled data will be given to you during the
labs the week of Oct 23 along with instructions for its analysis. You will also
be given instructions regarding the format and content of your report.
References:
Shreve, R.L., 1967. Infinite topologically random channel networks.
Journal of Geology, v.77, pp.397-414.
Shreve, R.L., !974. Variation of mainstream length with basin area in
river networks. Water Resources Research, v.10, pp. 1167-1177.
FIGURES FOR EXERCISE:
These figures are available in two formats: Word Document file and as a PDF file.
You may also view and print these figures from the
following two web pages:
Figure1
Figure 2
Last Updated August 18, 2000
by Eric Tappa at tappa@geol.sc.edu
This page copyright © 1995-2000, The Board of Trustees of the
University of South Carolina.
www.geol.sc.edu/courses/fall2000/geology_101_gardner.htm