Abstract: Amplitude Interpretation and Visualization of Three-Dimensional Reflection Data

Michael E. Enachescu

Digital recording and processing of modern three-dimensional surveys allow for relative good preservation and correct spatial positioning of seismic reflection amplitude. A four-dimensional seismic reflection field matrix R (x,y,t,A), which can be computer visualized (i.e., real-time interactively rendered, edited, and animated), is now available to the interpreter. The amplitude contains encoded geological information indirectly related to lithologies and reservoir properties. The magnitude of the amplitude depends not only on the acoustic impedance contrast across a boundary, but is also strongly affected by the shape of the reflective boundary. This allows the interpreter to image subtle tectonic and structural elements not obvious on time-structure maps.

The use of modern workstations allows for appropriate color coding of the total available amplitude range, routine on-screen time/amplitude extraction, and last display of horizon amplitude maps (horizon slices) or complex amplitude-structure spatial visualization. Stratigraphic, structural, tectonic, fluid distribution, and paleogeographic information are commonly obtained by displaying the amplitude variation A = A(x,y,t) associated with a particular reflective surface or seismic interval. As illustrated in this presentation with several case histories, traditional structural and stratigraphic interpretation combined with a detailed amplitude study generally greatly enhance our extraction of subsurface geological information from a reflection data volume. In the context of three-dim nsional seismic surveys, the horizon amplitude map (horizon slice), amplitude attachment to structure and "bright clouds" displays are very powerful tools available to the interpreter.

AAPG Search and Discovery Article #90982©1994 AAPG International Conference and Exhibition, Kuala Lumpur, Malaysia, August 21-24, 1994