Class hours: Wednesdays 12-2 and Thursdays 9-10; Place 1W01

Office hours: Wednesdays 9-12 and Thursdays 10-12; Place 1C01

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, 2nd edition, by D. Turcotte and G. Schubert. This book is an excellent reference for students going on in solid earth sciences.

Other useful reference books:

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.

A first course in continuum mechanics, by Y.C. Fung, Prentice Hall, 1969.

Elasticity, fracture and flow with engineering and geological applications, by J. C. Jaeger, Methuen & Co., 1962.

Div, Grad, Curl, and all that, by H. M. Schey, W.W. Norton and Co., NY 1973.

Along the way we will also read and discuss specific papers from the literature.

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

Gravity: Constraints on flexure, isostasy, geoid anomalies

Fluid mechanics: Mantle convection, isostatic rebound, continuum models of Earth deformation

Faulting: Elastic solutions, creep, aseismic deformation

Homework assignments:

1. Homework 1 (due Sept 11). Reading: Skim T&S chapter 1 through section 1-14; Read chapter 2.

2. Homework 2 (due Sept 25). Reading: Read T&S chapter 3.

3. Homework 3 (due Oct 16). Reading: Beavan et al (3), DeMets (4); Cox and Hart 85-158

4. Homework 4 (due Oct 30). Reading: T&S chapter 4. Forsyth (5 and 6), Lyon-Caen (7), Watts et al (8)

5. Homework 5 (due Nov 20). Download utah.xls; Reading: T&S chapter 7, Papers 9, 10, 11

Reading assignments:

1. Dalmayrac, B, and P Molnar, Parallel thrust and normal faulting in Peru and constraints on the state of stress, Earth Planet. Sci. Letters, 55, 473-481, 1981.

2. Mount, V. S., and J. Suppe, (PDF) State of stress near the San Andreas fault: Implications for wrench tectonics, Geology 15, 1143-1146, 1987.

3. Beavan, J., Tregoning, P., Bevis, M., Kato, T., and Meertens, C., Motion and rigidity of the Pacific plate and implications for plate boundary deformation, J. Geophys. Res. 107, 2261, doi:10.1029/2001JB000282, (2002). (PDF)

4. DeMets, C., Plate motions and crustal deformation, Rev. Geophysics, 365-369, 1995. (PDF)

5. Forsyth, DW, Comparison of mechanical models of the lithosphere, J. Geophys. Res., 85, 6364-6368, 1980. (PDF)

6. Forsyth, DW, Lithospheric flexure, Rev. Geophys. Space Phys., 17, 1109-1114, 1979. (PDF)

7. Lyon-Caen, H, and P Molnar, Constraints on the structure of the Himalaya from an analysis of gravity anomalies and a flexural model of the lithosphere, J. Geophys. Res., 88, 8171-8191, 1983. (PDF)

8. Watts, AB, JH Bodine and MS Steckler, Observations of flexure and the state of stress in the oceanic lithosphere, J. Geophys. Res., 85, 6369-6376, 1980. (PDF)

9. Parsons, B, and JG Sclater, An analysis of the variation of ocean floor bathymetry and heat flow with age, J. Geophys. Res., 82, 803-827, 1977. (PDF)

10. Molnar, P, and P England, Temperatures in zones of steady-state underthrusting of young oceanic lithosphere, Earth Planet. Sci. Letters, 131, 57-70, 1995. (PDF)

11. Peacock, SM, PE van Keken, SD Holloway, BR Hacker, GA Abers, and RL Fergason (2005) Thermal structure of the Costa Rica – Nicaragua subduction zone. Physics of Earth and Planetary Interiors, v. 149, 187-200. (PDF)