Analysis of the Seismic Coherence Attribute with Respect to Subsurface Fault Geometry

Mironova, Anastasia ¹; Thompson, Jenny ²; Krantz, Bob ²; Sinton, John ²; VanNostrand, Dominique ³; Bruhn, Ronald ¹; Johnson, Christopher ^4
1 Geology and Geophysics, University of Utah, Salt Lake City, UT.
² Subsurface Technology, ConocoPhillips, Houston, TX.
³ Alaska, ConocoPhillips, Anchorage, AK.
⁴ Scientific Computing and Imaging Institute, University of Utah, Salt Lake City, UT.

The objective of this study is to analyze the behavior of the seismic coherence attribute, particularly its relationship to subsurface fault geometry. Using data from the seismic survey of the Kuparuk River Field of the North Slope of Alaska as well as model data, a Monte Carlo method was applied to test the sensitivity of the coherence attribute in both settings. The coherence attribute responds differently to different fault geometries. Also, the ability of this attribute to resolve fault geometry depends on the selection of input parameters within the software suite used to compute it and on the frequency of sampling performed on the resulting coherence volumes. It was confirmed that the coherence attribute is affected significantly by the choice of migration methodology. Random noise, on the other hand, has a negligible effect on how faults are imaged with the coherence attribute. This work relates a geophysical attribute to a geologic property, a relationship that can be used for detailed interpretations of fault geometry from coherence attribute volumes in the future.

AAPG Search and Discovery Article #90090©2009 AAPG Annual Convention and Exhibition, Denver, Colorado, June 7-10, 2009