Objectives: This course is designed to introduce you to the basics of geodynamics and plate tectonics. The main objectives in this course are to get you to think of geological problems in terms of physics and mechanics and to provide you with a few tools necessary to begin applying physics to geologic problems. If we are successful then whenever you make a geological interpretation, you will ask yourself: Is it physically reasonable?
Main Textbook:
Geodynamics: Applications of Continuum Physics to Geological Problems by D. Turcotte and G. Schubert. This book is an excellent reference for students going on in solid earth sciences.
Reference Books and articles (on reserve):
Plate Tectonics: How it works, by A. Cox and R.B. Hart. This book introduces the mechanics of plate motions.
Global tectonics, by P. Keary and F. Vine.
Along the way we will also discuss specific studies; these papers will be placed on the reference shelf in the Huntington Library in the Science Center.
Important Dates
Jan 11. First class.
April 28 Last class.
Grade determination:
Exams: 20% each
Problem sets: 40%
Term paper and presentation: 20%
Late problems sets will be penalized by subtracting 20% of its total value per class that it is late. A problem set not turned in will get no credit; this can lower your final grade by several percentage points, so plan ahead.
Topics to be covered:
Review of continuum physics, forces, stress, vectors, etc.
Deformation: Strain, rotations, deformation gradient tensor
Plate motions: Poles of rotation, reference frames, measurement techniques
Inverse problems as applied to geodynamics and plate tectonics
Stress and strain in elastic and non-elastic materials, flexure of the Earth's lithosphere, subduction, seamounts, mountain belts
Diffusion: Heat transfer, flow in porous media, heating of subducted lithosphere, cooling of oceanic lithosphere, basin subsidence, thermal anomalies near faults (TS Chapter 4)
Gravity: Constraints on flexure, isostasy, geoid anomalies (TS Chapter 5)
Fluid mechanics: Mantle convection, isostatic rebound, continuum models of Earth deformation
Faulting: Elastic solutions, creep, aseismic deformation (TS Chapter 8)
Term papers and class presentation: A short report and class presentation on some topic in Geodynamics and Global tectonics are required. Topics of your own design are strongly encouraged but check with me first to ensure that it is appropriate. Give me a list of three topics you would like to do in order of preference. So that no two people are covering the same topic, I will then assign a topic to you from your list. Term papers should be approximately 10 pages of double-spaced, typewritten text and relevant figures. You should cover the theoretical framework of the topic, the relevant observational data, the agreement between the theory and data, what we have learned from the particular approach, and some recommendations for future research along these lines. You will also give a 15-minute presentation to the class on your topic.
Some suggested topics
Constraints on the thermal structure of subducting lithosphere.
Geodetic measurements and variability of strain along the San Andreas Fault.
On the controversy over one-layer or two-layer mantle convection.
Flexural models of the lithosphere.
Heat flow anomalies along the San Andreas fault.
Stress in the lithosphere.
Continuum models of continental deformation.
The driving mechanisms of plate tectonics.
Mechanics of accretionary wedge deformation.
Heat budget of the Earth.
Thermal evolution of thrust belts.
Mechanisms for the generation of deep earthquakes.
Constraints on the viscosity of the mantle.
Some helpful references
Fung, Y.C., A first course in continuum mechanics, Prentice Hall, 1969.
Jaeger, J.C., Elasticity, fracture and flow with engineering and geological applications, Methuen & Co., 1962.
Schey, H.M., Div, Grad, Curl, and all that, W.W. Norton and Co., NY 1973.
Policy on Cheating: We are required to state the policy of this class regarding cheating. It is expected that each student do his or her own work on homework assignments and exams. I encourage students to confer with each other for the purpose of gaining increased understanding of concepts. However, I expect that the written assignments will reflect the student's own thoughts and calculations; anything else will be considered cheating. If you use some resource (such as another student, a friend, or a publication) that contributes significantly to the solution of the problem, then I expect that proper credit will be given in the form of a citation. If cheating occurs, the student will receive an F grade for the class.