LECTURE OUTLINE GEOL 335.3, Term 2

SEISMOLOGY and GROUND PENETRATING RADAR

Instructor:

Igor Morozov

Geology 142; 966-5731

Course Texts:

• An Introduction to Applied and  Environmental Geophysics, 2-nd ed, 2011, J. M. Reynolds, John Willey & Sons
• Recommended: Introduction to Seismology, 2-nd ed., 2009, Shearer, P. M., Cambridge University Press.
• Recommended: Applied Geophysics, 1990, Second Edition, W. M. Telford, L. P. Geldart, R. E. Sheriff. Cambridge University Press.

A. INTRODUCTION  (lecture)

4 lectures

• Objectives and outline of the program
• Historical background of the different geophysical techniques
• Significance and scope of the application of the specific geophysical methods
• Review of the relevant reference literature and prominent scientific journals

General concepts (lecture)

• Key common concepts: Vectors, fields; Time and spatial series, Z- and Fourier transforms, Aliasing, Dynamic range (lecture)
• Convolution, Cross- and Autocorrelation, filtering (lecture)
• Signal and noise

B. SEISMIC OBSERVATION and EXPLORATION

17 or 18 lectures

Geometrical Seismics (lecture, homework assignment #1)

Wavefronts and rays

• Travel times
• Reflected, refracted, transmitted, and head waves
• Huygens' principle, Diffraction
• Fermat principle
• Snell's law
• Geometrical spreading

Seismic Waves (lecture, homework assignment #2)

• Mechanical properties of rocks, strain and stress, laboratory and in situ stress-strain relationships
• Importance to engineering applications, effects of lithology, density, porosity, temperature, and depths of burial
• Elastic wave theory - scalar and full wave equations, general aspects of wave propagation (lecture)
• Body waves, P and S waves
• Surface waves (lecture): Rayleigh, Love, Stonely - coherent noise or tools for imaging shallow subsurface
• Anisotropy and effects on wave propagation
• Waves in layered media

Seismic source (lecture) (homework assignment #3)

• Green's functions and Moment tensor
• Radiation patterns
• Source spectra
• Stress drop
• Earthquake magnitudes

Energy Sources in exploration (lecture) and Instrumentation (lecture)

• Onshore techniques- principles, application, advantages and disadvantages, economic and environmental issues
• Marine techniques- principles and applications
• Source requirements and design considerations
• Vibration principles
• Digital recording systems, Analog-to-Digital signal converters
• Signal detectors
• Design of target-oriented signal detection
• Recording, data storage and processing systems

Application Techniques

Refraction Methods (lecture, homework assignment #4)

• Physical Principles
• Survey procedures, onshore/marine, personnel, legal considerations
• Applications: exploration, engineering, environment and crustal environments
• Target related field survey design methods
• Interpretation techniques
• Case studies

Reflection Methods (lecture; homework assignment #5)

• Physical principles
• Field operation geometries, 2D/3D, onshore/marine
• Noise types, noise-recognition, signal-noise time and spatial relationships
• Design of signal detection systems and special problem oriented recording systems
• Velocity extraction methods, data dependent borehole techniques
• Corrections
• Data processing techniques (lecture): onshore/marine, spectral analysis, band limited/inverse filtering, correlation, velocity analysis, stacking
• Inversion and migration
• Data display techniques
• Interpretation procedures, correlation of seismic arrivals to geology, borehole geology, wireline data
• Synthetic seismograms modelling
• Practical examples: seismic images of faults, subsurface reefs, synclines-anticlines, seismic stratigraphic signatures, high resolution near surface buried channels and lithologic discontinuities
• Subsurface target definition, horizontal and vertical resolutions, imaging limitations
• Pitfalls in seismic interpretation

C. GROUND PENETRATING RADAR (lecture)

2 lectures

• High frequency electrical properties of rocks, EM wave propagation in ground, penetration, frequency/penetration. limitations
• Field operations, instrumentation
• Data handling and processing
• Engineering applications
• Case histories.