12.201 | Fall 2004 | Undergraduate

Essentials of Geophysics

Lecture Notes

The 5 chapters presented here started off as a set of rough lecture notes and are updated every year.

Chapter 1: The Earth in the Solar System (PDF)

1.1 Solar System Formation, Accretion, and the Early Thermal State of the Earth
1.2 Rotation and Angular Momentum
1.3 The Sun
1.4 Planetary Formation
1.5 Early Thermal State of the Earth
1.6 Radioactive Decay
1.7 Radiometric Dating
1.8 Radioactivity as a Heat Source
1.9 Meteorites and the Bulk Composition of the Earth
1.10 Chondrites
1.11 Secondary Processing
1.12 Achondrites
1.13 Irons and Stony-Irons
1.14 The Terrestrial Planets
1.15 One-dimensional Earth’s Structure
1.16 Lateral Heterogeneity in the Mantle

Chapter 2: The Earth’s Gravitational Field (PDF - 1.0 MB)

2.1 Global Gravity, Potentials, Figure of the Earth, Geoid
2.2 Gravitational Potential due to Nearly Spherical Body
2.3 The Poisson and Laplace Equations
2.4 Cartesian and Spherical Coordinate Systems
2.5 Spherical Harmonics
2.6 Global Gravity Anomalies
2.7 Gravity Anomalies and the Reduction of Gravity Data
2.8 Correlation between Gravity Anomalies and Topography
2.9 Flexure and Gravity

Chapter 3: The Magnetic Field of the Earth (PDF - 1.7 MB)

3.1 The Main Field
3.2 The Internal Field
3.3 The External Field
3.4 The Magnetic Induction due to a Magnetic Dipole
3.5 Magnetic Potential due to More Complex Configurations
3.6 Power Spectrum of the Magnetic Field
3.7 Downward Continuation
3.8 Secular Variation
3.9 Source of the Internal Field: The Geodynamo
3.10 Crustal Field and Rock Magnetism
3.11 Magnetization
3.12 Other Types of Magnetization
3.13 Magnetic Cleaning Procedures
3.14 Paleomagnetism
3.15 Field Reversals
3.16 Qualitative Arguments that explain the need for Core-mantle Coupling
3.17 Reversals: Time Scale, Sea Floor Spreading, Magnetic Anomalies
3.18 Magnetic Anomaly Profiles

Chapter 4: Seismology (PDF - 1.1 MB)

4.1 Historical Perspective
4.2 Introduction
4.3 Strain
4.4 Stress
4.5 Equations of Motion, Wave Equation, P and S-waves
4.6 P and S-waves
4.7 From Vector to Scalar Potentials - Polarization
4.8 Solution by Separation of Variables
4.9 Plane Waves
4.10 Some Remarks
4.11 Nomenclature of Body Waves in Earth’s Interior
4.12 More on the Dispersion Relation
4.13 The Wave Field - Snell’s Law
4.14 Fermat’s Principle and Snell’s Law
4.15 Ray Geometries of the Wave Field
4.16 Travel Time Curves and Radial Earth Structure
4.17 Radial Earth Structure
4.18 Surface Waves
4.19 Sensitivity Kernels
4.20 Excitation of Surface Waves
4.21 Dispersion: Phase and Group Velocity
4.22 Dispersion Curves
4.23 Seismology: Free Oscillations

Chapter 5: Geodynamics (PDF)

5.1 Heat Flow
5.2 Heat Flow, Geothermal Gradient, Diffusion
5.3 Thermal Structure of the Oceanic Lithosphere
5.4 Thermal Structure of the Oceanic Lithosphere (cont.)
5.5 Bending, or Flexure, of Thin Elastic Plate
5.6 The Upper Mantle Transition Zone

Course Info

As Taught In
Fall 2004
Learning Resource Types
Lecture Notes
Problem Sets