Geophysics - Reservoir Characterization

AVO in an Inversion World



  Dr Anthony Fogg (Arun Geoscience, United Kingdom)


  1 or 2 days


  Geophysics – Seismic Reservoir Characterization






  5 or 10 CPD points




Introduction video

A short version of this course has been recorded as an E-Lecture. Watching this video will give you a clear introduction of what the course is about and it will help you to prepare yourself if you are going to attend it!

Learn more about EAGE E-Lectures


Course description

AVO (Amplitude Versus Offset) analysis has been a key technology for derisking drill targets as it can potentially distinguish different fluids and lithotypes. Over time the application of the AVO technique has evolved and merged with seismic inversion methods so that today the traditional AVO analysis techniques have been superseded by the analysis of rock property volumes on the interpreter's work station. However, in order to derive these rock properties we still rely on the fundamental principles of AVO. This course covers the basics of AVO theory and how it is used to create attributes or inversion volumes from seismic reflection data that reveal the rock and fluid characteristics of the sub-surface. The course is not mathematical, but does review some simple equations that help the student understand how AVO is applied to create quantitative measurements from surface seismic data and interpret those results in terms of rock physics - often referred to as Quantitative Interpretation (QI).


Course objectives

Upon completion of the course, participants will be able to understand the commercial application of AVO and have a basic understanding of seismic inversion methods and reservoir characterization, know what the results tell you in terms of rock physics and the possible limitations and errors in those results. Participants will be in a better position to critically analyse the results of such studies presented to them by contractors or partner companies. Participants will also be shown techniques to enable them to create some simple reconnaissance AVO data volumes using tools that are available in most interpretation packages.


Course outline

  • What is AVO and how does it occur;
  • Measuring and classifying AVO responses;
  • Incorporating AVO in to seismic inversion;
  • Rock physics & elastic impedance;
  • Generating rock physics data volumes from seismic inversion results;
  • Seismic processing considerations – velocity, migration, bandwidth;
  • Impact of anisotropy, VTI and HTI, and harnessing the effects;
  • Case studies – conventional and unconventional (shale) resources.


Participants' profile

Interpreters, geologists, geophysicists and other geoscience disciplines who have an interest in understanding how AVO, rock physics and seismic inversion is applied in real world studies.



Participants should have some knowledge of what seismic data is (pre-stack and post-stack) and what well log data is.


About the instructor

Dr Anthony Fogg

Anthony has provided integrated rock physics, AVO, inversion and interpretation studies to the oil and gas sector since the mid 1990's. He obtained his first degree in Geophysics (Geological) from the University of Leicester (UK) and his PhD in Geophysics from the University of Leeds (UK) where he was sponsored by British Coal. Anthony has an oil company background working as an explorationist in the UK North Sea for Amoco UK Exploration Ltd and as a QI consultant for Statoil ASA in Norway. He also spent a period working on and offshore undertaking wireline logging operations. For the last twenty years he has led geoscience teams in the provision of bespoke rock physics studies for private, national and multi-national corporations in basins across the globe. He has presented many technical papers and case studies at industry conferences and in journals and he has taught a variety of courses in the geosciences, including the industry renowned Hampson-Russell courses. He has given EAGE courses since 2012 and lectured to non-geoscience organisations, schools, universities and adult learning colleges promoting greater understanding of geology and geophysics by the general public. He also works as a Research Fellow at the University of Southampton in the Department of Ocean and Earth Sciences.


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