A quick scan of the SEG web site shows that the phrase “seismic petrophysics” has been used explicitly in the title of a paper or abstract six times, the earliest of which was by Williams et al. in 1996 (“The Hugoton cross-well survey; A direct look at stratigraphy, seismic petrophysics and shale anisotropy”). However, the first attempt at a definition and an expanded description of “seismic petrophysics” was published by Wayne Pennington in The Leading Edge in 1997 (“Seismic petrophysics: An applied science for reservoir geophysics”). He defines seismic petrophysics as follows: “…the purposeful application of rock physics theory, as calibrated by laboratory and well measurements, to the interpretation of seismic data…”