Abstract: The specification describes methods of and apparatus for converting seismic data to migrated seismic depth sections. The apparatus includes a curve follower for following lines of continuity on seismic time sections which represent reflections from particular subsurface interfaces. The curve follower generates signals representing occurrence times and horizontal distances at successive increments along the lines of continuity. These signals are applied to a digital computer which performs a migration operation and generates signals representing the attitude, actual depth and horizontal displacement of successive points on the interfaces. An automatic plotter plots reflection segments at the correct attitude, actual depth and horizontal displacement to produce the migrated seismic depth section.

Abstract: In a seismic data processing system, seismic data in channel-sequential format intensity modulates the electron beam of a cathode-ray tube. A photographic drum plotter provides a recording of the seismic data displayed on the face of the cathode-ray tube. A screen of multilined squares is placed in contact with the photographic film on the drum plotter so that the seismic data is recorded in a half-tone, variable-density format.