To be eligible for the Virgil Kauffman Gold Medal, the recipient must have made an outstanding contribution to the advancement of the science of geophysical exploration during the previous five years. In Dave Hale's case, clearly both the contribution and the contributor can be described as outstanding. The contribution centers around Dave's work at Stanford where he received his Ph.D. under the direction of Jon Claerbout.
     During graduate school at Stanford, Dave established himself as the primary worker on the theory and application of dip moveout processing or partial migration. While not the originator of the method, his innovations moved it quickly into the mainstream
     of geophysical technology.
     Of Dave's work, Jon Claerbout says: "Proper imaging of reflection seismic data requires a knowledge of the seismic velocity. But finding the velocity is itself a goal of the imaging process. This bootstrapping is an area of intense commercial competition and academic theorizing. In the early 1970s, John Sherwood introduced a concept, dip moveout, but did not reveal the underlying analysis. I recognized the value of the concept and to some degree, with my student, Öz Yilmaz, gave it an analytic foundation. But the foundation was weak. Then Fabio Rocca found a geometric description of how to define the travel times correctly to all angles. But few people understood Rocca's theory, and it did not deal satisfactorily with amplitudes and phases. Dave Hale then invented a Fourier analysis approach to the problem that got correct all angles, amplitudes, and phases. Hale's method also had the virtue of being readily understood, and people nowadays put Hale's solution in the class of Bob Stolt's landmark work on migration by Fourier transform. Following Hale's first presentation, the number of workers in this formerly arcane area rapidly ballooned. It became the most active area of data processing research and development in the SEG. Of the thirty students I have guided to Ph.D., there is no doubt that Dave's work has had the greatest impact on the activities of researchers at other institutions."
     Don Paul, manager of Chevron's geophysical research says: "Dave was a member of the Geophysics Division at Chevron Oil Field Research in La Habra, California, from 1983 to 1988. His research in super-computer applications to velocity analysis and prestack seismic imaging made significant technical contributions to Chevron's exploration efforts in several areas of complex structures." He further states, "His thesis, Dip moveout by Fourier transform, has become the reference work on the subject."

     Dave received his B.S. in physics from Texas A&M in 1977 and worked for Western Geophysical in seismic research from 1977 to 1979. It was from this background that he was able to contribute through the Stanford Exploration Project.
     Ken Larner, then with Western and now a professor at the Colorado School of Mines, says: "Since the award is for a major technical contribution within the past five years, it should be added that since his development of the DMO method, Dave has contributed greatly to the profession through the clarity and completeness of his insights into not only the DMO process but also seismic imaging in general. He has conveyed these insights in the highly popular and well received SEG Continuing Education course on DMO and in the outstanding graduate courses in seismic migration and data processing that he has conducted at Mines.
     "Dave is a great guy! His change of career paths from industry to academia was motivated primarily by a strong desire to share his knowledge with students and to help develop research skills among graduate students. His courses are a joy, a remarkable blend of theory, computation, and the practical. Students not only learn from him exciting insights into theory, they also get a great sense of why things are done the way they're done in industry. As a result, he prepares students well to contribute
     effectively in industry.

     "Any activity that bears Dave's imprint is stamped with excellence. So far, our profession has had only a small taste of the many breakthrough contributions yet to come from him."
     Dave is currently an associate professor of geophysics at Mines, but no discussion of Dave can be considered complete without mention of the support he has received from his wife, Laura, who is a geophysicist in her own right. After Laura received her M.S. degree from Stanford in geophysics, she was employed by Chevron in San Francisco. Interestingly, it was Laura that introduced both partial migration and Dave to Chevron. While working on a difficult and complex seismic line from the Gulf of Suez, she
     strongly suggested that the solution to the problem was partial migration and that Dave Hale (at Stanford) could process the line through DMO and greatly enhance the data. I don't recall whether the data were improved or not, but I do remember Laura's dedication to partial migration (and to Dave).
     I am honored in being asked to write this citation, and I thank Jon Claerbout, Don Paul, and Ken Larner for their input. I know these people have been important to Dave, and we believe there will be future citations for this highly inventive and energetic person.

      L. C. Lawyer