Module Details

The information contained in this module specification was correct at the time of publication but may be subject to change, either during the session because of unforeseen circumstances, or following review of the module at the end of the session. Queries about the module should be directed to the member of staff with responsibility for the module.
Title Geophysical Data Modelling
Code ENVS386
Coordinator Professor RT Holme
Earth, Ocean and Ecological Sciences
R.T.Holme@liverpool.ac.uk
Year CATS Level Semester CATS Value
Session 2022-23 Level 6 FHEQ First Semester 15

Aims

Ability to create geophysical models from data. Practical experience in inversion of mathematically linear problems, with knowledge of how to approach more general nonlinear problems.

Understanding of the limitations of such models, and how they should be interpreted, with particular reference to model non-uniqueness and instability. Optimisation theory, and its application to interpretation of geophysical models. Time series analysis with non-Fourier methods.

Understanding of basic statistics, confidence.


Learning Outcomes

(LO1) Knowledge and understanding of mathematical fundamentals of data modelling, including eigenanalysis, statistical foundations and implications of model existence and nonuniqueness for interpretation.

(LO2) Interpretation of statistical results and Geophysical modelling of real data sets

(LO3) Ability to invert a large data set to give a geophysical model

(LO4) Programming skills, in particular the ability to work in a unix/linux environment with shell programming

(S1) Problem solving skills

(S2) Numeracy

(S3) Communication skills

(S4) IT skills


Syllabus

 

One. Optimisation, including Lagrange multipliers
Two. Mathematical methods problem session.
Three. Eigenvalues and eigenvectors, particularly of real symmetric matrices
Four. Mathematical methods problem session
Five. Error analysis and basic probability and statistics. The Normal distribution and Central Limit Theorem
Six. Central limit theorem demonstration practical
Seven. Hypothesis testing, regression, Chi-squared.
Eight. Least squares application to a geophysical problem.
Nine. Introduction to inversion through linear algebra.
Ten. The generalised matrix inverse
Eleven. Least-squares inversion worked examples (one)
Twelve. Philosophy of inverse theory: existence, uniqueness, construction and stability
Thirteen. Least-squares foundations of the generalised inverse.
Fourteen. Least squares inversion worked examples (two)
Fifteen. Practical solution: Ranking and winnowing, regularisation. Numerical methods (Cholesky decomposition).
Sixteen. Data error covariance. A priori model covariance. Solution resolution and covariance.
Seventeen. Project session one - Introduction to problem and solution formation.
Eighteen. Interpretation through framing the inverse problem as an optimisation problem - impliations for error estimates and practical bounds on results. Introduction of hypothesis testing as an appropriate solution to this problem.
Nineteen. Alternative methods of error estimation - bootstrapping.
Twenty. Project session two - Solution space investigation.
Twenty One. Examples of hypothesis testing applied to inverse theory.
Twenty Two. Introduction to non-linear inversion, including simulated annealing. Outliers.
Twenty Three. Project session three - Resolution, covariance, the eigenproblem.
Twenty Four. Earthquake location - worked example
Twenty Five. Introduction to tomography as a non-linear inverse problem. Splines.
Twenty Six. Non-linear in version example
Twenty Seven. Practical examples of inverse theory
Twenty Eight. Time series analysis with optimisation - splines
Twenty Nine. Advanced topics, including how course material leads into "Big data" and Machine learning.


Teaching and Learning Strategies

Teaching Method 1 - Lecture
Description: Description and definition of methods.
Attendance Recorded: Yes

Teaching method 2 - Pre-recorded lectures
Description: Basic content covered in recorded lectures to allow more timem for interactive teaching in main lecture

Teaching Method 3 - Laboratory Work
Description: Application of methods, particularly to mathematical problems and the modelling of the magnetic field of Neptune
Attendance Recorded: Yes
Unscheduled Directed Student Hours (time spent away from the timetabled sessions but directed by the teaching staff): 18

Teaching Method 4: Online office hours
Two hours of availability each week for discussion. To be extended if there is demand,


Teaching Schedule

  Lectures Seminars Tutorials Lab Practicals Fieldwork Placement Other TOTAL
Study Hours 16

        24

24

64
Timetable (if known)              
Private Study 86
TOTAL HOURS 150

Assessment

EXAM Duration Timing
(Semester)
% of
final
mark
Resit/resubmission
opportunity
Penalty for late
submission
Notes
Written Exam. There is a resit opportunity. Standard UoL penalty applies for late submission. This is an anonymous assessment. Assessment Schedule (When): Semester 1  120    60       
CONTINUOUS Duration Timing
(Semester)
% of
final
mark
Resit/resubmission
opportunity
Penalty for late
submission
Notes
1000 word report There is a resit opportunity. Standard UoL penalty applies for late submission. This is an anonymous assessment. Assessment Schedule (When) :Semester 1, Week 9.    20       
Maths fundamentals (optimisation and eigensystems)         
Problem set - statistics and regression         
Problem sheet - generalised least-squares         
Problem sheet - tomography         

Recommended Texts

Reading lists are managed at readinglists.liverpool.ac.uk. Click here to access the reading lists for this module.