University of Texas at Austin

Exploring for Subtle Mission Canyon Stratigraphic Traps with Elastic-Wavefield Seismic Technology

A study funded by the U.S. Department of Energy and Vecta Exploration

Bob A. Hardage, principal investigator; Milo M. Backus, Michael V. DeAngelo, Robert J. Graebner, Jeffrey A. Kane, Paul E. Murray, and Diana C. Sava


Example of coherency attribute data demonstrating that P and C modes image different stratal surfaces and depositional facies associated with an incised-valley depositional system. Seismic times shown on the figures define image depth within the respective data volumes and emphasize the need for developing accurate techniques for correlating image surfaces from different seismic data volumes.

This study is funded by the U.S. Department of Energy and Vecta Exploration. In its subcontract to Vecta Exploration, Inc., the Exploration Geophysics Laboratory (EGL), is developing a new seismic technology to explore for subtle Mission Canyon oolitic limestone reservoirs in the Williston Basin. This technology will be based on the acquisition and application of full-elastic (9-component) seismic data. Mission Canyon reservoirs are elusive targets when exploration is based on conventional compressional (P) wave seismic data. The attraction of 9-component (9-C) seismic data is that three shear (S) wave modes can also be used for target imaging: SH-SH (horizontal shear), SV-SV (vertical shear), and P-SV (converted shear) modes. Work at EGL has shown that each mode of an elastic wavefield can, and often does, image stratal surfaces across a target interval differently than do other elastic modes. Thus, any of the S modes can depict seismic sequences and seismic facies that are not observed using P waves. This rich, expanded source of stratigraphic and lithofacies information in full-elastic seismic wavefields needs to be utilized in Mission Canyon exploration. The objectives of this study are to acquire, process, and interpret 9C3D seismic data across Mission Canyon plays, develop relationships between drilling objectives and elastic-wavefield attributes, drill confirmation wells, and then share research findings so that full-elastic seismic technology can be applied to improve oil exploration across other areas.

For more information, please contact Mark Shuster, principal investigator.
Telephone 512-471-7090; e-mail

February 2003