Biography Citation for SEG Honorary Membership
Contributed by Jon Claerbout
Over the years, I have come to appreciate Fabio Rocca's visits to Stanford enormously. He never fails to leave behind exciting and original research projects, many of which grow into Ph.D. theses. Fabio has a knack for seeing possibilities in sketchy proposals, summarizing their essential problems, and suggesting the best tools to solve them. His collaborators are amazingly productive during his visits. Computers bog down late into the night, and seminars must be scheduled more frequently. Fabio managed the Stanford research group during my last sabbatical leave and produced the thickest volume of research reports yet.
Fabio seems to have collaborators throughout Europe and the U.S. One of his secrets is his ability to visualize graphically, geometrically, and intuitively whatever seismic signal processing algorithm he is likely to encounter. For example, he introduced what I call "Rocca's smile, an early and clear conceptual model for prestack partial migration and dip moveout. He is also quick to find analogies between exploration geophysics and the other fields in which he works: biomedical signal processing, television, and synthetic aperture radar which he first discovered could be migrated like seismic data.
Fabio received his Dottore in Ingegneria in 1962 (cum laude) from the Department of Electronics in the Politecnico di Milano. Since then he has been a professor in that department: in 1963, as a teaching assistant; in 1967, as an associate professor; in 1975, as a full professor of radio techniques; and now as a professor of digital signal processing. He became department head in 1975 and then moved on to the University Board of Regents in 1980.
His productive work at the university has not prevented Fabio from collaborating formally with many other organizations. He consulted with AGIP, the Italian national oil company, from 1968 to 1983, and acted as president of the Osservatorio Geofisico Sperimentale in Trieste, Italy, from 1983 to 1984. He was also a visiting professor at Stanford in '78, '79, '82, '83, '87, and '88. He was president of the European Association of Exploration Geophysicists in 1987-88, and was associate editor of Geophysical Prospecting from 1981 to 1985.
Fabio's more than 85 published papers cover seemingly every area of applied geophysical signal processing. Back when one-dimension methods still filled the literature, Fabio and Emanuele Cassano used multichannel techniques for the suppression of multiple reflections and for the spectral estimation of the depths of magnetic anomalies. Fabio has a deep understanding of statistical and numerical tools. Giuseppe Bolondi, S. Zanoletti, and Fabio prepared an especially robust automatic contouring algorithm for irregularly sampled data in faulted areas. He worked with Robert Godfrey and Francis Muir to construct a very realistic model of the impedance log as a Markov process.
Fabio has developed many innovative seismic migration methods with original applications to noise suppression, velocity analysis, and survey design. Early on at AGIP Fabio, Bolondi, and S. Savelli developed frequency-domain and recursive methods. Later, they and E. Loinger used offset continuation to break prestack migration into several robust steps. With S. M. Deregowski, Fabio simplified the subject of dip moveout and prestack partial migration for many people. With Dan Rothman and Stew Levin, Fabio demonstrated that a 15 degree migration can still allow an accurate residual migration. He motivated Bill Harlan and myself to isolate diffractions for wide-angle velocity analyses. Fabio and Shuki Ronen saw that the antialiasing properties of dip moveout can allow sparse recording geometries.
Throughout his career Fabio has followed my preferred road to "inversion" by breaking it into reliable and easily interpreted pieces (the opposite of global inversions). For instance, with Loinger and John Toldi, he saw that stacking velocities can be inverted tomographically for lateral changes in interval velocities. He has a good eye for those features of a tomographic algorithm which distinguish transmission velocities from structural changes. Fabio and Marta Woodward have begun to generalize tomographic methods for bandlimited raypaths ("sausages"), which are sensitive to edges of velocity anomalies. Fabio was also one of the earliest to propose and then record real-time surveys similar to VSP's by using the drill bit as a seismic source.
Fabio abhors overspecialization and recently led in the foundation of the European Association of Petroleum Geoscientists. He believes that "as the computer learns mathematics and the smart geophysicist learns geology and geochemistry, the geologist will find it easier and easier to learn geophysics." I hope that Fabio will find many new partners in research.