3-D Reservoir Characterization with Horizon Visualization and Coherency/Inversion Animations; GGRB, Wyoming

FAVRET, PAUL and STEVE CLAWSON

The Echo Springs Field and surrounding Wamsutter Development Area in the Greater Green River Basin (GGRB) of Wyoming, USA are currently being developed with 3-D seismic using coherency data, visualizations, and inversion animations.

For structural and stratigraphic interpretations, the Amoco coherency cube and surface visualization are used. Animations of horizon consistent coherency extractions from Amoco's coherency cube, demonstrate many of the complex channels, deltas, and faults in the productive section. Visualization technologies, primarily represent surface visualization and interpretation in Geoquest Geoviz, are used to identify individual faults and their controls on stratigraphy throughout the section. The visualizations demonstrate significant basement structural controls over shallower stratigraphy in the productive section which wells are very difficult to map with normal 2 dimensional mapping techniques.

Horizon consistent inversion volumes demonstrate the successive transgressive and regressive cycles through the productive Mesa Verde section. The inversion volume displays interval velocities, then color coded to indicate individual rock types. The animation starts at the lower Almond-Ericson boundary illustrating this prolific fluvial section, moving up section, the inversion illustrates the lower Almond regression and its associated channels and deltas. Then the transgressive, tight middle Almond marine tongue is seen moving into the area from east to west. Next the inversion illustrates a second regression with associated channels and deltas and finally the upper almond transgression is seen passing from east to west, depositing the Echo Springs Bar sand in the western part of the survey. 

AAPG Search and Discovery Article #91021©1997 AAPG Annual Convention, Dallas, Texas.