Robert H. Stolt is an American geophysicist and the inventor of (f,k) migration.
Award Citation for Bob Stolt's Honorary Membership in SEG
Contributed by John R. Hopkins
I consider it an honor to write this citation for Bob Stolt's Honorary Membership in SEG.
I first met Bob Stolt in early 1974 while interviewing for a job at Conoco. I could tell right away that I was in the presence of an intellectual giant and hoped for a chance to work for a company that hired people like Bob. Being hired by Conoco was the beginning of my good luck. Bob's good luck started when he married Donna. He has a great sense of humor, although it's often so "dry" that only the most attentive listeners understand.
He earned a B.S. in mathematics and physics from Wyoming University in 1966 and a Ph.D. in theoretical physics from Colorado University in 1970. He also served as a post doctoral fellow at CU for a year before joining Conoco in 1971.
Bob has contributed much to the geophysical technologies that Conoco and the industry have used and continue to use today. Over the years, Bob has been a technical leader and a leader of people and often both. Under his managerial leadership, Conoco was able to remain competitive in the geophysical sciences during the "bust" years. When Bob assumed a supervisory position in 1977, he was still working on f-k migration. After publishing the landmark paper in 1978 on f-k migration, frequently referred to as "stolt migration," he started to also work in seismic inversion. This work led to another internationally recognized paper in 1981 with R. W. Clayton.
During the 1980s, Bob was developing computer processing algorithms for dip moveout and amplitude-preserving prestack cascading time migration. Bob's work in migration and inversion culminated in coauthorship (with Al Denson) of a classic textbook published in 1986.
Once more powerful computers were available, Bob began to develop new methods in inversion, partial migration, demigration, and multiple removal. He had such a unique understanding of the relationships between computing speed and his developments that he was able to focus on techniques that could be implemented cost-effectively on the available machines. This insight into the linkage between computers and geophysics is rare.
Bob received the Reginald Fessenden Award in 1980 for his pioneering work in f-k migration. During 1979-1980 he served as a consulting professor and acting director of the Stanford Exploration Project. He helped that prestigious group in developing breakthroughs in inversion and multiple attenuation. Bob has served SEG in a number of capacities including Associate Editor, then Editor of Geophysics, Chairman of the Publications Committee, Technical Program Chairman of the 1994 Annual Meeting, and as a member of the Research Committee since 1991. He is an Honorary Member of the Geophysical Society of Tulsa.
Recently, Bob was selected to receive the DuPont Lavoisier Medal, an award recognizing great technical and creative accomplishments and contributions over many years which resulted in a measurable business impact of enduring significance. The winners represent the best scientists and engineers in DuPont's history, and Bob is one of the few recipients who were active employees at the time of their award.
Bob is now the highest ranking technical person in Conoco. In his new role as senior research fellow, he has resumed his brilliant work in multiple attenuation, and I expect that SEG members will see more breakthroughs from his "leading edge" work in years to come.
Once again, it's an honor for me to write this citation for Bob Stolt, and it's been fun and a great privilege to have interacted with this principle-centered man for 24+ years.
Award citation for the SEG Reginald Fessenden Award, 1980
This award, designated the SEG Medal Award at its inception in 1961, was renamed in 1977 to recognize Reginald Fessenden for his role as the originator of the concept of reflection and refraction surveying in 1917. It is awarded to a person who has made a specific technical contribution to exploration geophysics, such as an invention or a theoretical or conceptual advancement, which, in the opinion of the Honors and Awards Committee and the Executive Committee, merits special recognition.
R. H. (Bob) Stolt was selected for the Reginald Fessenden Award because of his work in wave equation migration and his F-K migration paper, "Migration by Fourier Transform." Bob's F-K migration makes use of Fourier transforms in both space and time, resulting in an algorithm which is both computationally efficient and accurate for steeply dipping events. Once the two-dimensional Fourier transform was taken, Bob made use of the fact that the tangent of the apparent dip angle is equal to the sine of the true dip angle. Migration in F-K space then becomes a matter of frequency shifting determined by this simple geometrical relation. The migrated section in space and time is then obtained by an inverse transform. The algorithm becomes, with a little physical insight, a clean and efficient work of art and not a clumsy, brute force approach consisting of many Fourier transforms.
The paper was received by the Editor of GEOPHYSICS in September 1976, presented to the Stanford Exploration Project (SEP) in May 1977, and finally published in February 1978. However, because of the release through SEP, the results were widely known and used much earlier than the publication date by purchase of software based on Bob's analysis. As a result of this work, Bob was asked to direct the SEP for the 1979-1980 academic year while Jon Claerbout was on sabbatical. In a characteristic manner, Bob decided to accept this new challenge leaving behind almost all of his old books, old problems, and old ideas, with some concept of interacting with the students at Stanford and examining anew the ideas of scattering theory. This new venture and interaction was very successful, and the exciting new results may force us all to learn more about scattering theory, Gelfand-Levitan algorithms, and even Dirac notation!
Bob Stolt is one of those quietly competent physicists who enjoys his family, religion, science, and fellowship with others in rarely balanced fashion. His contentment with himself and his confidence in his own abilities allows him to face the outside world with an open mind and an unpretentious manner. These qualities, coupled with such a warm personality and willingness to help others, makes his advice constantly sought after from his peers, since seldom can one obtain such valued advice and counsel so painlessly. With the possible exception of Einstein, he holds no one in too high esteem and, similarly, holds contempt for no man. His sense of humor makes him a pleasure to work with and often allows him to become the "soft shoe" act in any sequence of presentations. It is impossible to sleep through one of his talks for fear you might miss one of his subtle jokes, a tricky bit of mathematical physics, or his physical insight which suddenly explains the entire phenomenon.
It is hoped that Bob Stolt's new work on scattering and inverse scattering theory will be as useful and applicable to geophysics as his work on F-K migration.