GEOL 757 - Advanced Seismic Imaging and Tomography

Course Outline Call #89067 Instructor: J. Louie, 217 LME, 784-4219 11:00-12:15 TR LMR355 Fall, 2008
Learning Objectives: This course completes after Geol 706 ``a coherent overview of the whole field of data processing as it is used in petroleum exploration,'' (Claerbout, 1985) and is the most advanced course in seismic exploration at the University of Nevada. The course goes beyond the two texts by including introductions to tomography and finite-difference modeling developed by Profs. Robert W. Clayton and John E. Vidale, and material on Kirchhoff migration from Prof. John Louie. Further objectives from Claerbout (1985):
``As it happens, waves are marvelously geometrical objects, and much can be learned with little mathematical analysis. But you should begin the book having previous familiarity with calculus, complex exponentials, and Fourier transformation.
``Your knowledge won't be complete if you don't know some opinions as well as the facts. You will be getting opinions as well as facts when I explain the discrepancies between theory and industrial practice, and when I explain what should work but doesn't seem to.
``Prospecting for oil begins with seismic soundings. The echoes are processed by computer into images that reveal much geological history. Worldwide, echo sounding and image making constitute about a four-billion-dollar-per-year activity.
``... the skills developed in this book, computer implementations of concepts from physics, will always be of general utility.''

Lectures: Two 75-minute lectures each week. See also the schedule below from 2001.

Texts:

  1. Jon Claerbout, 1992, Earth Soundings Analysis: Processing versus Inversion (PVI), Blackwell, ISBN #0-86542-210-9, out of print. Available from the instructor and in the DeLaMare Library. Read the text on-line at Stanford (or in DVI format for your LaTeX reader here, if you are logged into the Seismology Sun system). Here is a 4 Mb PDF version built by the author in 2006.

  2. Jon Claerbout, 1985, Imaging the Earth's Interior (IEI), Blackwell, ISBN #0-86542-304-0, out of print. Available from the instructor and in the DeLaMare Library. Read it on-line at Stanford; or download your own copy in PDF format, in parts through pages: 50; 100; 150; 200; 250; 300; 350; 400 (up to 1.7 Mb each).

  3. Jon Claerbout, 1999, Geophysical Estimation By Example (GEE), Free. Available only on-line from Stanford; some sections in in a directory of PDF files on the Seismo server.

The lecture notes will be available prior to each lecture for you to copy.

URL: http://www.seismo.unr.edu/ftp/pub/louie/class/757-syll.html

Grading: Term Projects 100%
I encourage any student needing to request accommodations for a specific disability to please meet with me at your earliest convenience to ensure timely and appropriate accommodations.

Original, individual projects are required and should be selected in consultation with the instructor. Possible projects vary widely and can take the form of literature reviews, theoretical demonstrations, application development, or data analysis. For each project the student should turn in a five to ten page project report, plus figures and an abstract, that properly reviews and cites appropriate background literature, fully describes the methods, presents the project results, and discusses their applicability and significance. See the instructor for project suggestions, which can also be found within the lab assignments linked from the Geol 706 syllabus.

  • Conjugate Gradient Applications
    • Univariate Problems
      • Crosstalk
      • Noise, Deconvolution
      • Nonstationarity
    • Conjugate Operators
      • Matrices, Products
      • Mappings, Interpolation
      • Inversion, Tomography
    • Model Fitting
      • Least Squares
      • Iteration, Gradients
      • Deghosting, Synthetics
    • Time-Series Analysis
      • Shaping Filters, Noise
      • Prediction Error Filters
      • Blind Deconvolution
      • Weighted Error Filters
      • Noise Crosscorrelation
    • Missing Data
      • One-Dimensional Filters
      • Spectral Preference
      • Two-Dimensional Interpolation
      • Spatial Predictors

  • Multi-Offset Methods
    • Seismic reflection experiment geometry
    • Sorting and gathers
    • Survey sinking
      • Reciprocity
      • Dip and wavenumber
      • Double square root (DSR) equation
      • Imaging condition
      • F-K multi-offset migration
      • Cross-correlation and virtual sources
    • Separation of the DSR equation
      • Normal moveout (NMO)
      • Dip moveout (DMO)
      • Velocity analysis
    • Prestack partial migration
      • NMO as a dip filter
      • Fourier representation of DMO
      • DMO algorithm
    • Slant stack (p-tau or array phasing)
      • Impulse response
      • Radon transform
      • Inverse slant stack
      • Refraction velocity inversion
      • Refraction microtremor analysis
    Multi-Offset (continued)
    • 3-d Kirchhoff migration
    • Signal/noise separation and enhancement
      • Coherence
      • Multi-dimensional linear transforms
      • Bayesian signal enhancement

  • Lateral Velocity Variation (as time permits)
    • Statics & ray coverage
    • Transmission tomography
      • Applications
      • Radon transform
      • Tomographic approximation
      • Linearization, velocity variation
      • Back projection
      • Noise cross-correlation and group-velocity mapping
    • Traveltime Optimization
      • Nevada methods (not Monte-Carlo)
      • First arrivals
      • Reflection times
      • Reflection coherency
    • Diffraction tomography
      • Born approximation
      • WKBJ & far-field approximations
      • Inversion by back projection
      • Iteration
      • Approximations to elastic WE
    • Velocity-structure tradeoff
    • Finite-difference modeling
      • Acoustic and SH
      • Elastic
      • Boundary conditions
      • Source imposition
      • Stochastic media
      • Community Velocity Models
    • Wide-angle experiments
      • Multiphase recording
      • Shallow effects
      • Frequency vs offset
      • Amplitude vs offset
      • Poisson's ratio and lithology

All of the codes used in the textbooks are accessible on-line from the Stanford Exploration Project. We also have local copies of: codes from PVI; codes from GEE; and HTML documentation on SEPlib.

For the Radon tomography example discussed in the lectures, the gradient-step, steepest-descent, conjugate-gradient, and Hestenes and Stiefel iteration scripts are available

Fall 2001 Schedule

 Geol 757 meets each Tues. and Thurs. 9:30-10:45 in LMR 355 except as noted below:
DayDateSchedule Change
TuesdayAugust 28First lecture, 11-12:30, LME 426
Thursday30David Simpson lecture, 1:30-2:30, LME 322d
ThursdaySeptember 20Finish Lab 1
Tuesday25No Class, SCEC Meeting
Friday28Make-up Lecture, 11:00-12:30, LMR 355
ThursdayOctober 4Lab 2 DUE, in class
Tuesday9No Class, PASSCAL Meeting
Friday12Make-up Lecture, 11:00-12:30, LMR 355
Friday12Lab 3 DUE, in class
Thursday18No Class, UTEP Meeting
Friday19Make-up Lecture, 11:00-12:30, LMR 355
Thursday25Lab 4 DUE, in class
ThursdayNovember 1Lab 5 DUE, in class
Monday5Make-up Lecture, 1:30-2:45, LMR 253
Tuesday6No Class, Walnut Creek demo
Thursday8Project title DUE, in class
Tuesday13MIDTERM, in class
Monday15Project outline DUE, in class
Thursday22Thanksgiving Day, no class
FridayDecember 7Make-up Lecture, 1:30-2:45, LMR 355
Friday7Last class, evaluation at 1:30, lecture at 1:40
Tuesday11AGU Meeting, no class
Tuesday18PROJECTS DUE 5:00 PM in LME 217

Reference List to Inspire Projects