Peter S Kaufman¹, Eddie McAllister², Rob Smallshire²
(1) Schlumberger-Doll Research, Ridgefield, CT
(2) Rock Deformation Research Group, University of Leeds

Abstract: Collection and visualization of 3D digital geologic data sets: An example from the Moab fault zone, UT

Outcrop and core-scale evidence demonstrates that fault zones are complex, with the main slip plane typically being surrounded by clusters of subordinate size faults that collectively define a fault damage zone. The techniques of digitally capturing and visualizing the geologic complexity of a fault damage zone will be demonstrated using outcrop exposure of the Moab fault, a major seismic-scale fault in southeastern Utah. Excellent footwall exposures of the Jurassic Entrada sandstone were examined in detail to characterize the subseismic fault populations within a damage zone at the scale of an individual reservoir fault block. Traditional field geology methods were combined with high-resolution differential global positioning system to collect outcrop data in conjunction with accurate location information. These data can be visualized using a 3D viewing environment to display different elements of the damage zone in their relative spatial positions including individual minor fault strands, statistical traverses, topography, and photo images. By moving interactively through the damage zone visualization, a geologist can take a virtual field trip to examine the complex internal architecture of the sub-seismic faults in their true spatial context. Associating outcrop structural geologic data with precise spatial coordinates also supports detailed statistical analysis. This detailed geologic information collected digitally from outcrop analogs can be used as a reference benchmark for addressing a variety of faulted reservoir problems such as reservoir characterization, well bore stability analysis, seismic forward modeling, or borehole image interpretation.

AAPG Search and Discovery Article #90914©2000 AAPG Annual Convention, New Orleans, Louisiana