Geology 141: Marine Geology

Fall 2008
Tuesday & Friday 11:30-12:45
Lab Friday 2:30-5:20

Instructor: David M. Dobson
Office: Frank 215C
E-mail: ddobson@guilford.edu
Phone: 316-2278
Office Hours: Mon 1-3, Wed 12-1, Thu 10-11
or make an appointment or just drop by
 Click Here for Lab 5 - Biostrat Program
Syllabus Information   Lecture Topics and Notes
Course Description and Objectives:  Students should leave this course with a thorough understanding of the ocean and of the many roles it plays in shaping the surface of our planet.  We will discuss the challenges and rewards of oceanographic research.  We will explore the origin and history of the oceans, the tectonic forces that shape the ocean basins, and the rocks and minerals that make up the ocean floor.  We will examine the living organisms of the oceanic world, and we will study the ocean’s control of global and regional climate.  We will also explore human exploitation of marine resources and the dangers we may cause the world and ourselves.

Laboratories:  There will be weekly laboratory sessions in which we expand upon lecture topics and allow you to try your hand at geologic and oceanographic research.  There will be a variety of types of activities, including working with rock samples and specimens, conducting chemical analyses, working with maps and computers, running simulations, and analyzing data.  Each lab will weigh equally toward your final grade unless otherwise specified.  Weekly lab assignments are due at the beginning of the following lab; i.e., the lab you are given on a Monday is due at the beginning of lab the following Monday.

Late Work:  Work will be accepted after the due date for up to 10 days.  For each day or portion of a day the work is late, a penalty of 5% of the student’s grade will be assessed, to a maximum penalty of 50%.  No late work will be accepted after 10 days except in emergency circumstances (major health problems or the equivalent).  Note that it is ALWAYS better to turn in what you have than not to turn anything in at all.  I’m generous with partial credit, but I have to give you zero credit if I’ve got zero to work with.

TextIntroductory Oceanography, 10th edition, Thurman and Burton, Ó 2001, Prentice Hall Publishing Company, 554 pp.  Other readings may be assigned as needed.  You may be able to get by with a 9th edition, which may also be considerably cheaper; the book doesn’t change too much between editions.  The chapter numbers are somewhat different, however; make sure you’re reading the right material.

Exams:  There will be two hour exams and one final exam in this course.  The final exam will cover all course topics but will emphasize the final section of the course after the second exam. Exams are based more on lectures and discussions than on reading, but the reading serves as an important supplement and expansion on the course materials.

Attendance:  The lectures cover the things I think are most important, and want you to learn. Missing one means you miss a major part of the course.  If you miss more than four lectures, you may be asked to drop the class. 

Grading:  Grades in this course will be determined as follows.  Grading will be on a straight scale with a supporting curve.  For example, a student who scores 85% of the total available points is guaranteed a B.  However, if that student is in the top 15% of the class, she will get an A- or A instead.

Item                           Weight

First exam..................... 15%

Second exam................ 15%

Final exam.................... 20%

Labs.............................. 40%

Class participation........ 10%

Grade   % Range   Minimum
% of class

A  

90-100

15

B  

80-89

35

C  

70-79

35

D  

60-69

10

F  

<60

 --


Pop Quizzes:  There will occasionally be quizzes on subjects from lectures or reading taken in the first few minutes of class in place of roll-call attendance.  Good performance on these quizzes will improve your final grade.  Poor performance or missing the quizzes may hurt your class participation grade.

Workload:  Guilford College expects average students to work three hours per week (including class time) for each credit hour.  This is a four-credit course.  So, for a C+/B- grade, this comes out to about 12 hours of work per week for a typical student, about six and a half of which are outside of class (reading, working on labs, researching, reviewing with others). You won’t always work exactly 12 hours every week, and the different course activities may not take you the same amount of time as they do other students.  However, an example of the breakdown could be something like this:

Item

Time

Class meetings

2.5 hours

Lab meeting

3 hours

Reading and study

3 hours

Completing lab assignments

3 hours

Reviewing for tests

0.5 hours

Guilford Honor Code:  Guilford’s Honor Code, “I have been honest and I have observed no dishonesty,” applies to all of your work for this class.  For the purposes of this class, this means that all work you turn in must be your own unless I explicitly state that you're allowed to turn in work as a group. With the exception of quizzes and exams, you may consult with others and work with others in doing your work. It is acceptable to work in groups; it is not acceptable merely to copy answers or solutions.  Under no circumstances are you to turn in someone else's work, in full or in part, as your own.  Violations of the honor code will be referred to the Judicial Board or other appropriate college unit.  At a minimum, a violation will result in zero credit and, at the instructor’s option, a failing grade in the course.

Lecture topics for First Exam
(
Book Chapters 1-5)

 

Lecture topics for Second Exam
(Book Chapters 6-11 plus parts of 12 and 13)

  • Light absorption in seawater (blue and some green penetrate, red and violet absorbed rapidly)
  • Ocean structure
  • Seawater
  • Heating and cooling of water
  • Atmospheric and oceanic circulation and climate
    • Differential heating of poles and equator
    • Vertical movement of air (high and low pressure, deserts and rainy areas)
    • Horizontal movement of air (winds and wind bands)
    • Coriolis effect (from rotation of Earth)
    • Surface currents and gyres (big circular current patterns)
    • Temperature and speed of ocean currents (western intensification)
  • Waves
  • Tides
    • Two theories:
      • Equilibrium theory -- Tides are primarily caused by bulges in the ocean surface created by the sun and moon. Each of these creates one bulge on the side facing it and one bulge on the opposite side. As the earth spins, different spots enter the area of the bulge and experience high tides.
      • Dynamic theory -- This theory covers the features of tides not explained by the equilibrium theory. The dynamic theory corrects for the fact that tides occur within ocean basins and are affected by land and the ocean floor.
    • Tides are caused about 2/3 by the moon, 1/3 by the sun
    • At low latitudes tides are semi-diurnal (two high and two low tides per day)
    • At high latitudes tides are diurnal (one high and one low tide per day)
    • In between, tides are mixed, with one high high tide, one low high tide, one high low tide, and one low low tide
    • When sun, earth, and moon are in alignment (syzygy) the tidal range is greatest. This condition is called a spring tide.
    • When the sun and moon create bulges perpendicular to each other, the tidal range is smallest. This is a neap tide.
  • Coastal erosion and engineering
    • Longshore current (waves break at an angle and run back straight, so zig-zag path means water is along the coastline)
    • Longshore transport (longshore currents also move sand and other sediments with them)
    • Coastal construction (especially groins) can be harmful if longshore transport isn't taken into account
    • Harbor construction can fail to protect ships if wave behavior (reflection, diffraction) is not considered
  • Marine biology and ecosystems
    • Photosynthesis and chemosynthesis
    • Oxygenation and Banded Iron Formations (BIFs)
    • Autotrophy vs. heterotrophy
    • Coral and reef communities - symbiotic algae, temperature requirements, growth forms, etc.
    • Photosynthesis vs. Chemosynthesis
    • Q10 rule (10°C change = double metabolic rate)
  • Living in marine environment - evolution of marine species
    • Benefits
      • Support
      • Waste removal
      • Readily available water
      • Food floats by (filter feeding)
    • Drawbacks
      • Cold temperature
      • Salinity (particularly for spawning fish or in estuaries)
      • Lack of light

Additional Lecture topics for Final Exam
(Book Chapters 12-18)

NOTE: Final exam is CUMULATIVE! You need to know the earlier stuff too.

  • Plankton, Nekton, Benthos
  • Food chains/webs, upwelling
  • Nutrients and the Redfield Ratio
  • Bermuda Triangle - many possible causes
    • Bad luck - it's a stormy, highly traveled area
    • Compass confusion - it's one of the few places where magnetic north is the same as true north
    • Methane bubbles - there are lots of frozen methane deposits underwater which can melt, leading to bubbles in the water which can make the water less dense). This could also affect planes.
  • Whales - evolution, adaptation, and human hunting (click for lecture notes) (click for slides)
  • Law of the Sea and Fisheries (click for slide show)
  • Additional Topics
    • Greenhouse Effect - incoming sunlight hits Earth and is re-radiated as heat; this heat gets trapped by carbon dioxide (CO2), methane (CH4), and other gases which are transparent to sunlight
      • Global warming is bad for some people (e.g. coastal regions) but good for others (e.g. Siberians)
      • Earth's heat balance (incoming light vs. heat emission)
      • Carbon dioxide
      • Methane
      • Positive feedback (e.g. albedo, clathrates)
      • Negative feedback (e.g. evaporation and clouds)
    • Ozone loss (ozone = O3) and ultraviolet radiation (incoming UV light is normally blocked by the ozone layer, but chlorofluorocarbons have been destroying ozone, allowing damaging UV light to reach the surface of the Earth)
      • More UV light is bad for all living things, because it causes genetic damage (which can lead to cancer in complex organisms)
      • Chlorofluorocarbons (CFCs)
      • Ozone dynamics (absorbs ultraviolet light)
      • Ozone holes over poles

Click Here for the answers to Problem Set II

 

Geology 141: Marine Geology
Schedule of lectures and laboratories
 
Week Tuesday Friday Topic Readings Lab Topic
1 19-Aug 22-Aug Introduction: Scientific Analysis and Properties Ch. 1 1. Maps and Navigation
2 26-Aug 29-Aug History of Marine Exploration Ch. 2 2. Rocks and Minerals
3 2-Sep 5-Sep Origin of Earth and Oceans Ch. 3 3. Plate Tectonics
4 9-Sep 12-Sep Plate Tectonics Ch. 3 4. Marine Sediments
5 16-Sep 19-Sep Marine Provinces and Sediments Ch. 4-5 5. Oil Exploration
6 23-Sep 26-Sep Seawater and Ocean Environments EXAM 1 Friday 9/26 Ch. 6 6. Biostratigraphy
7 30-Sep 3-Oct Atmospheric and Oceanic Circulation Ch. 7-8 7. Lake Coring
8 7-Oct 10-Oct Waves and Tides Ch. 9-10 8. Disaster Movies
9 14-Oct 17-Oct Fall Break
10 21-Oct 24-Oct Coasts and Shores Ch. 11-12 9. Seawater Properties
11 28-Oct 31-Oct Marine Organisms Ch. 13, 15, 16 10. Waves and Tides
12 4-Nov 7-Nov Marine Ecosystems                                EXAM 2 Friday 11/7 Ch. 14, 15, 16 11. Pollution Simulation
13 11-Nov 14-Nov Fisheries Ch. 17 12. Marine Life
14 18-Nov 21-Nov Marine Resources Ch. 17 13. Global Warming Conference
15 25-Nov 28-Nov Ice Ages and Climate Change Ch. 18 Thanksgiving - No lab
16 2-Dec 5-Dec Concluding thoughts   Reading Day - No lab
Exams 10-Dec Final Exam - High Noon

 

Exam Dates:        
  Fri. 9/26 First Exam    
  Fri. 11/7 Second Exam    
  Wed. 12/10 Final Exam (12:00 noon)