The topics of seismic inversion and AVO (Amplitude Variations with Offset) have a long history in seismic analysis and interpretation. The two topics are now grouped under the term QI, which stands for Quantitative Interpretation. Their history dates to the 1960’s when post-stack inversion, which transforms stacked seismic amplitudes into acoustic impedance, was first developed. In the 1980’s, we discovered that pre-stack amplitudes could be used to infer fluid properties of the reservoir, and this led to the development of AVO analysis, which fits a curve to the seismic amplitudes based on a linearized set of equations. The equations behind AVO were then extended to inversion, and the pre-stack inversion technique was developed to extract acoustic impedance, shear impedance and optionally, density, from the pre-stack gathers.

In this course, I will describe the theory of post-stack inversion, AVO analysis, and pre-stack inversion, and will illustrate these techniques using both simple numerical examples, and real data examples from around the world. These examples will include oil and gas exploration, SAGD, geothermal, and CCUS. I will also discuss the topic of rock physics, which will set the groundwork for our study of inversion. Although the primary focus will be on deterministic inversion, in the final sections of the course I will discuss more advanced techniques like stochastic inversion and inversion using machine learning.
Outline

The topics covered in this course will be:
1. Introduction to seismic inversion.
2. An overview of rock physics.
3. Post-stack deterministic inversion.
4. Amplitude variations with offset (AVO).
5. Pre-stack deterministic inversion.
6. Applications to oil and gas exploration and SAGD.
7. Applications to geothermal and CCUS.
8. Stochastic inversion methods.
9. Machine learning applied to seismic inversion.
10. Summary and Conclusions.