The Power of 3D Stereo Contour Mapping

S. Parker Gay Jr., Ben Opfermann, and John C. Young

"3D" perspective viewing of data, with its many variations and manipulations as carried out on state-of-the-art computer workstations, represents a major advance in visualization. However, an even more powerful technique for viewing geological and geophysical data is 3D stereo contour mapping, first developed using manual methods in the 1940's and greatly refined in the last two decades with modern computer-plotter techniques.

Many features can be seen in 3D stereo that are not recognizable on even the best work- station displays. For example, on the gravity map of the western United States a previously unrecognized (and as yet unpublished) circular 2100-km diameter gravity low is readily seen through a complex pattern of superimposed shorter wavelength anomalies. On magnetic maps linear features corresponding to unrecognized regional sutures and major oil fields are seen. On structure contour maps strike-slip fault offset, not previously recognized by nationally prominent structural geologists, are obvious even to the uninitiated, and errors in structure contour map constructions are immediately visible to the casual viewer.

It is possible to combine 3D stereo techniques with workstation technology, and small data sets have been shown quite effectively in this fashion. However, visualizing data sets of large areas, a major advantage of 3D stereo, awaits development of higher resolution, wider screen CRT's or other hardware. At present, it is best done in map fashion.

AAPG Search and Discover Article #91019©1996 AAPG Convention and Exhibition 19-22 May 1996, San Diego, California