Robert W. Clayton
Professor of Geophysics, Emeritus
B.A.Sc., University of Toronto, 1973; M.Sc., University of British Columbia, 1976; Ph.D., Stanford University, 1981. Assistant Professor of Exploration Geophysics, Caltech, 1981-85; Associate Professor, 1985-89; Professor of Geophysics, 1989-2023; Professor Emeritus, 2023-. Executive Officer for Geophysics, 1987-94; Acting Director, Seismological Laboratory, 1989; 2008-09; Deputy Director, 1989-90; Academic Officer, 2008-19.
Research Summary
Crustal and upper mantle seismology; using array seismology to determine the properties of subduction and rifting; tectonics of Mexico and Peru; measuring temporal variations in seismic properties using ambient noise; marine geophysics; exploration geophysics; near-surface geophysics.
Research Options
Geophysics;
Profile
Research website: /~clay/homepage.html
Crustal Seismology
The research interests of Robert W. Clayton are in determining variations in Earth properties from seismic waves. This research is being pursued on many scales, from the fine scale of crustal and exploration seismology to the larger scale of regional seismology.
Large-scale seismic experiment provide some of the highest resolution image of crustal structure. In Southern California, there have been three major large-scale surveys which have produced important results: the trans-Sierra transect, and the LARSE I and II surveys across the San Gabriel Mts, north of Los Angeles.
Array Seismology
Another intriguing aspect of the array is the possibility of providing early warning of strong ground shaking. Events detected in one part of the network can potentially be used to provide warning in other parts.
Numerical Wave Simulation
Wave propagation in 3D has become fairly routine. The current limitation is in determining a velocity model with sufficient resolution to match the accuracy of the calculations. We have participated in the development of the SCEC 3D velocity model which contains the basins and other features in the greater Los Angeles area.
We have also developed a technique for computing reciprocal Green's functions which allows us to simulate the effect of multiple sources with one numerical calculation. This allows us to economically try different scenarios on a given fault.
Publications
Please see Robert Clayton's publications page:
Ge 111 ab. Applied Geophysics Seminar and Field Course.
6 units (3-3-0); second term. Prerequisite: instructor’s permission. 9 units (0-3-6); spring break, third term. Prerequisite: Ge 111 a; , 2023-24.
An introduction to the theory and application of basic geophysical field techniques consisting of a comprehensive survey of a particular field area using a variety of methods (e.g., gravity, magnetic, electrical, GPS, seismic studies, and satellite remote sensing). The course will consist of a seminar that will discuss the scientific background for the chosen field area, along with the theoretical basis and implementation of the various measurement techniques. The 4-5-day field component will be held in spring break, and the data analysis component is covered in Ge 111 b. May be repeated for credit with an instructor’s permission.
Instructors: Clayton, Simons
Instructors: Clayton, Simons
Ge 102. Introduction to Geophysics.
9 units (3-0-6); second term, 2022-23.
Prerequisites: Ma 2, Ph 2, or Ge 108, or equivalents.
An introduction to the physics of the earth. The present internal structure and dynamics of the earth are considered in light of constraints from the gravitational and magnetic fields, seismology, and mineral physics. The fundamentals of wave propagation in earth materials are developed and applied to inferring Earth structure. The earthquake source is described in terms of seismic and geodetic signals. The following are also considered: the contributions that heat-flow, gravity, paleomagnetic, and earthquake mechanism data have made to our understanding of plate tectonics, the driving mechanism of plate tectonics, and the energy sources of mantle convection and the geodynamo.
Instructors: Clayton, Gurnis
Instructors: Clayton, Gurnis
Ge 11 d. Introduction to Earth and Planetary Sciences: Geophysics.
9 units (3-0-6); second term, 2022-23.
Prerequisites: Ch 1, Ma 2 a, Ph 2 a.
An introduction to the geophysics of the solid earth; formation of planets; structure and composition of Earth; interactions between crust, mantle, and core; surface and internal dynamics; mantle convection; imaging of the interior; seismic tomography. Although Ge 11 abcd is designed as a sequence, any one term can be taken as a standalone course.
Instructors: Clayton, Gurnis
Instructors: Clayton, Gurnis
Ge 111 ab. Applied Geophysics Seminar and Field Course.
6 units (3-3-0); second term. Prerequisite: instructor’s permission. 9 units (0-3-6); spring break, third term. Prerequisite: Ge 111 a; , 2022-23.
An introduction to the theory and application of basic geophysical field techniques consisting of a comprehensive survey of a particular field area using a variety of methods (e.g., gravity, magnetic, electrical, GPS, seismic studies, and satellite remote sensing). The course will consist of a seminar that will discuss the scientific background for the chosen field area, along with the theoretical basis and implementation of the various measurement techniques. The 4-5-day field component will be held in spring break, and the data analysis component is covered in Ge 111 b. May be repeated for credit with an instructor’s permission.
Instructors: Clayton, Simons
Instructors: Clayton, Simons
Ge 165. Geophysical Data Analysis and Seismic Imaging.
9 units (3-0-6); first term, 2022-23.
Prerequisites: basic linear algebra and Fourier transforms.
Introduction to modern digital analysis: discrete Fourier transforms, filters, correlation, convolution, deconvolution and auto-regressive models. Imaging with seismic reflection and refraction data, tomography, receiver functions and surface waves.
Instructor: Clayton
Instructor: Clayton
Ge 263. Computational Geophysics.
9 units (3-0-6); first term, 2022-23.
Prerequisites: introductory class in geophysics, class in partial differential equations, some programming experience.
Finite-difference, pseudo-spectral, finite-element, and spectral-element methods will be presented and applied to a number of geophysical problems including heat flow, deformation, and wave propagation. Students will program simple versions of methods.
Given in alternate years; not offered 2022-23.
Instructors: Clayton, Gurnis
Instructors: Clayton, Gurnis
Ge 102. Introduction to Geophysics.
9 units (3-0-6); second term, 2021-22.
Prerequisites: Ma 2, Ph 2, or Ge 108, or equivalents.
An introduction to the physics of the earth. The present internal structure and dynamics of the earth are considered in light of constraints from the gravitational and magnetic fields, seismology, and mineral physics. The fundamentals of wave propagation in earth materials are developed and applied to inferring Earth structure. The earthquake source is described in terms of seismic and geodetic signals. The following are also considered: the contributions that heat-flow, gravity, paleomagnetic, and earthquake mechanism data have made to our understanding of plate tectonics, the driving mechanism of plate tectonics, and the energy sources of mantle convection and the geodynamo.
Instructors: Clayton, Gurnis
Instructors: Clayton, Gurnis