- Copyright © 2002 Society of Exploration Geophysicists
The workshop's first session reviewed seismic, medical, and space imaging technology with two presentations from each field—one to introduce basic concepts and demystify the jargon, and one to describe the state of the art.
Bob Stolt's introductory seismic overview presented the basic concepts of 2- and 3D, pre- and poststack, time and depth migration, and gave simplified tutorials on different integral- and difference-equation migration techniques. “Seismic depth imaging of complex geological structures” by Larry Lines emphasized the complexity of the earth as a propagating medium, and the need for sophisticated processing to produce accurate structural images. Complex geologic structures (which often involve steeply dipping beds, folded structures, and anisotropic velocities) usually invalidate many conventional processing methods. However, according to Lines, Kirchhoff, f-x, and reverse-time prestack depth imaging perform adequately (at a minimum) when a reasonable velocity model and data with coherent signals are available. Figure 1 shows the final interpretation for a prestack depth migration of a triangle zone feature in the Alberta Foothills. A complete description of the data and imaging can be found in “Seismic imaging and velocity analysis for an Alberta Foothills seismic survey” by Yan and Lines (Geophysics, 2001).