ROSE School: Computational Geophysics and Data Analysis

Prof. Dr. Heiner Igel and Moritz Beyreuther, LMU Munich

Last update: December 01, 2009

 

November 30 – December 11, 2009

 

Scope: The course aims to provide students with an understanding of the principles of digital signal processing, filter theory and the application of spectral methods in the analysis of geophysical data. Topics include discrete Fourier transforms, convolution, power spectra, transfer functions, covariance, correlation, Laplace transforms, Z-transforms, filters, deconvolution, basic statistics, model fitting via singular valued decomposition and probabilistic methods. The lectures are complemented by practicals with data examples from major recent earthquakes (e.g., the great Andaman M9.3 earthquake), as well rotational seismology, and computational wave propagation.

 

Tentative Lecture Plan (L – Lecture, T- Tutorial)

 

Day/Time

9:00-10:30

11:00-12:30

14:00-15:30

Mon, 30. Nov

L1

L2

T1

Tue, 1. Dec

L3

T2

L4

Wed, 2. Dec

L5

T3

L6

Thu, 3. Dec

L7

T4

L8

Fri, 4. Dec

L9

T5

T5

 

 

 

 

Mon, 7. Dec

L10

T6

L11

Tue, 8. Dec

L12

L13

T7

Wed, 9. Dec

L14

T8

T8

Thu 10. Dec

Exam

 

 

Fri 11. Dec

 

 

 

 

Minimum total lecture time:  21 hrs

Minimum total tutorial time:  12 hrs

 

Lecture and tutorial outline, literature, additional material and links:

 

Literature:

 

Most of the graphics are taken from the following books, additional material is given with each lecture or tutorial:

Stein and Wysession, An introduction to seismology, earthquakes and earth structure, Blackwell Scientific (Chapts.  6, 7 and appendix) see also http://epscx.wustl.edu/seismology/book/ (several figures here taken from S+W).

Shearer, Introduction to Seismology, Cambridge University Press, 1990, 2nd edition 2009 (section on data processing and appendices)

Tarantola, Inverse Problem Theory and Model Parameter Estimation, SIAM, 2005 (probabilistic inversion, examples in the appendix)

Gubbins, Time series analysis and inverse problems for geophysicists, Cambridge University Press (e.g., Z-transforms, geophysical applications)

Scherbaum, Basic concepts in digital signal processing for seismologists (e.g., seismometer equation, instrument corrections).

Scherbaum, Of Poles and Zeros, Fundamentals of Digital Seimology, Springer 2007

Schuster: Seismic Interferometry (Cambridge University Press), using correlation techniques for tomography

 

Excellent material can be found online here:

http://www.seismo.ethz.ch/staff/jclinton/GDP07/GDP07.html  (Course on Geophysical Data Analysis by John Clinton, ETH, e.g. Laplace- and z-transforms)

 

 

Links to pdfs with the folders containing slides and additional material are given below. Note that some of the slide shows are unfinished and will be further updated. Also note that maths details will be given on the board.

 

Note: links below not operational until Tue November 24!

 

Week 1:

 

Day 1:

L1:   Introduction: What are the current hot topics of seismology and what role do computations and data analysis play?

L2:   Mathematical background for data analysis and inverse problems

T1:   Maths exercises: complex numbers, linear algebra, matrices and vectors, eigenvector analysis, applications to geophysical problems

 

Day 2:

L3:   Data in seismology: networks, observables.

T2:   Introduction to Python, ObsPy and Arclink

L4:   Seismic instruments, instrument response

 

Day 3:

L5:   Generating synthetic seismograms: an introduction

T3:   1-3D acoustic wave propagation using finite differences

L6:   Spectral analysis: Foundations

 

Day 4

L7:   Applications of spectral analysis in seismology

T4:   Spectral estimation with data from the Great Sumatra Earthquake 2004

L8:   Filtering: Be careful!

 

Day 5:

L9:   (Almost everything is a) Linear system: convolution and de-convolution, transfer functions, and other transforms

T5:   Filtering seismic data: Low-pass, high-pass, band pass.  Instrument correction

 

 

Week 2:

 

Day 1:

L10:  Auto- and cross-correlations: applications in geophysics

T6:  Time-frequency analysis. Correlation techniques.

L11: Geophysical inverse problems: an introduction

 

Day 2:

L12: Probabilistic inverse problems: the Bayesian approach

L13: Monte Carlo methods: sampling the model space

T7:   Simple inverse problems, metropolis algorithm, simulated annealing, genetic algorithms

 

Day 3:

L14: Overall Review, Outlook, Current research topics

T8:  Final project work

 

Day 4:

Examination