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You will get more out of a commercial consultation with us if you first familiarize yourself with the ideas in the following public literature, which also establishes our claim for world-class expertise.

Porosity. This 1985 paper, the first of the following to be cleared for publication by Amoco, was specially selected by GEOPHYSICS for inclusion in its Golden Anniversary issue. It explains how to model the seismic properties of rocks with both equant and fracture porosity, in a way that is consistent with Biot theory.

Fluids, Lithology. This discussion extended over 13 years, beginning with a TLE Round Table Discussion entitled "Poisson was not a Geophysicist!", and ranging widely over many topics in seismic rock physics, with emphasis on the (minor) role played by Poisson's Ratio in the analysis.

Pore Pressure. This paper describes a unique " global algorithm" for predicting subsurface pore pressure using seismic data.  It commonly predicts the occurrence of "subsurface fluid compartments", i.e. extended volumes with a local hydrostatic gradient, and an elevated head.  But, all pore pressure prediction algorithms are imperfect, so it is important to apply several independent algorithms, which preferably rely on different input datasets, e.g. Vp/Vs.

Understanding Anisotropy. This set of Lecture Notes supported the 2002 SEG/EAGE Distinguished Instructor Short Course; here is the Introduction. The Notes themselves (2nd Edition) are for sale through the SEG, as are recordings of the lectures, in VHS and DVD formats.

Polar Anisotropy. This 1986 paper established the modern era in anisotropy studies. It is the single most-cited paper in the history of Geophysics; if you Google 'Thomsen parameter', you will find over 300,000 hits. It is essential reading for any study of seismic anisotropy. (There is a bizarre phenomenon for SV-waves in strongly anisotropic media, first discovered over 100 years ago, but not really understood until 2002.This new understanding may yet turn out to have useful implications.)

P-wave AVO.  One consequence of this advance in understanding is a profound conclusion regarding Amplitude Variation with Offset. It was realized early on that the polar-anisotropic term in AVO was potentially as large as the isotropic terms.  But this insight was ignored for 20 years, with an entire sub-industry being built on isotropic AVO analysis (neglecting the anisotropic term), since there was no way to estimate it in field data. However, 20 years later an algorithm has been discovered to do just that; it is the subject of a UH patent application.

Azimuthal Anisotropy (P-waves).  Azimuthal AVO ("AVOAz") was discovered by Thomsen in 1981, and analyzed in an internal Amoco report. With the recent expansion of wide-azimuth seismic surveys, the effect is seen to be ubiquitous; this 2006 paper offers the best confirmation that the observed effect corresponds to real fractures in the subsurface. In 1995, the effect of fractures on seismic wave propagation was explained theoretically (significantly revising earlier theory), and successfully predicted (not fitted) experimental data which had been obtained separately.

Azimuthal Anisotropy (S-waves). Azimuthal anisotropy causes two modes of shear waves to propagate at near-vertical incidence, rather than one. Here is the first explanation of (the now well-known) "Alford Rotation" solution to this phenomenon of shear-wave splitting, and the first report of the phenomenon in exploration field data. If the azimuth of the symmetry axis varies with depth, then a layer-stripping procedure is required.

Converted Waves used to be esoteric phenomena of interest only to academics. But, with the establishment of the feasibility of 4-Component Ocean Bottom Seismic surveying, they became an essential part of the seismic toolkit. The industry learning curve has been rapid, paid for by the ability of converted waves to image inside gas chimneys, gas clouds, etc. This 1999 paper was named "EAGE Best Presentation" for establishing the concepts of "C-waves", "registration", "gamma-effective", "vector infidelity", and "diodic velocity". Since then, the list of seismic problems which can be profitably addressed with 4C OBS data has expanded considerably, to also include:

This list continues to grow, but one essential learning of the past decade is that inclusion of anisotropy (both polar and azimuthal) in the analysis is crucial for most C-wave processing.


Fluid dependence.  For over 50 years, the standard theory for understanding the fluid dependence of seismic velocities has been that due to Biot and Gassmann.  But the experimental support for that theory is very thin. Now it develops that the theory itself is not quite right; we have been doing it a bit wrong all these years! This 2010 refinement to B/G challenges the experimental community to a program of experiments for determining the extra parameter required.


Shale resource. With the recent realization that shale can be a reservoir rock, people have begun to understand the importance of anisotropic rock physics. An important advance was the 2012 realization that the fluid dependence of seismic anisotropy is complicated, but there is an unexpected simplicity as regards the anisotropic parameter h.  Another 2012 paper clarified the (indirect!) relation between log data and Young’s modulus for anisotropic shales, and challenges the experimental community to a program of experiments to estimate brittleness from data that we can actually measure in the field.


Electromagnetic exploration. CSEM has now been shown to be a viable adjunct to seismic exploration, since it provides a near-direct detection of subsurface hydrocarbons.But there might be a better way to do it, based on the deep connections between seismics and EM. Since, at low frequencies, EM velocities are comparable to seismic velocities, seismic-style processing based on the moveout of the data, is an alternative to conventional amplitude inversion. See more discussion here.


These ideas have helped to establish the modern paradigm of exploration geophysics. If this public material makes you think that these ideas might help you with your particular problem, contact us.


Just as importantly, they establish the current base for further progress in exploration geophysics. If you think that your particular problem is not fully addressed by these ideas, contact us anyway; the way to make progress is through confronting particular problems, finding general solutions through the failure of the old ideas.