AVO (SEG Investigations in Geophysics No. 16) by Satinder Chopra and John Castagna begins with a brief discussion on the basics of seismic-wave propagation as it relates to AVO, followed by a discussion of the rock-physics foundation for AVO analysis including the use of Gassmanns equations and fluid substitution. Then, the early seismic observations and how they led to the birth of AVO analysis are presented. The various approximations for the Zoeppritz equations are examined, and the assumptions and limitations of each approximation are clearly identified. A section on the factors that affect seismic amplitudes and a discussion of the processing considerations important for AVO analysis are included. A subsequent section explores the various techniques used in AVO interpretation. Finally, topics including the influence of anisotropy in AVO analysis, the use of AVO inversion, estimation of uncertainty in AVO analysis, converted-wave AVO, and the future of the AVO method are discussed. Equally helpful to new entrants into the field as well as to seasoned workers, AVO will provide readers with the most up-to-date knowledge on amplitude variation with offset.

About the Author

Satinder Chopra is chief geophysicist (reservoir) at Arcis Seismic Solutions, TGS, Calgary. In the last 30 years, he has worked in regular seismic processing and interactive interpretation but has spent more time in special processing of seismic data involving seismic attributes, including coherence, curvature and texture attributes, seismic inversion, AVO, VSP processing, and frequency enhancement of seismic data. His research interests focus on techniques that are aimed at characterization of reservoirs. He received master of science and master of philosophy degrees in physics from Himachal Pradesh University, Shimla, India. Chopra is a member of SEG, CSEG, CSPG, Canadian Heavy Oil Association, EAGE, AAPG, Association of Professional Engineers, Geologists and Geophysicists of Alberta, and the Texas Board of Professional Geoscientists. John P. Castagna founded Fusion Geophysical, a geophysical contractor specializing in integrated seismic analysis, in 2000. In February 2010, he founded Lumina Geophysical, leading the industry in seismic spectral analysis, quantitative interpretation, and reservoir characterization. He currently holds the Robert Sheriff Chair of Geophysics at the University of Houston. Castagna is a graduate of Brooklyn College, where he earned a bachelor of science degree in geology in 1976 and a master s degree in high-temperature geochemistry in 1981. He completed his doctoral degree in exploration geophysics at the University of Texas at Austin in 1983. His main technical interest is quantitative seismic analysis in exploration and reservoir characterization, and he specializes in exploration geophysics research and development. He is widely known for his work in direct hydrocarbon detection and reservoir characterization.