Exploring for Subtle Mission Canyon Stratigraphic Traps with Elastic-Wavefield Seismic Technology
The objective of this project is to develop a new seismic technology that will improve exploration for Mission Canyon oolitic limestone stratigraphic traps in the Williston Basin. This technology involves the acquisition of nine-component (9-C) seismic data that will allow independent P, SH, SV, and C images of geologic targets to be constructed. The integrated use of these images provides more seismic-sequence and seismic-facies information than does conventional P-wave seismic technology. The broader goal is to develop these methods for use in many other stratigraphic environments.
Vecta Exploration, Ltd., Dallas, TX
Institut Français du Pétrole, Paris, France
The project performer has successfully acquired 10 square miles of 9-C seismic data and has processed the data through a subcontractor. The project performer has successfully contracted with Institute Français du Pétrole in order to develop a more rigorous multicomponent seismic interpretation product. Final interpretation of the Mission Canyon sequence was completed in 2006; however, the anomaly was of insufficient size to be a commercial target. Therefore, the project performer analyzed the shear data for anisotropy within the Bakken formation and has successfully drilled a horizontal well through anomalous zones in the middle member of the Bakken formation. The well is currently being tested; although, there has not been any indication of hydrocarbons at this point. With higher oil prices today, there has been renewed interest in the Mission Canyon prospect, and a separate well may be drilled to test such in the near future.
Using elastic-wavefield seismic technology, researchers will be able to construct new lithofacies-sensitive attributes from P and S seismic data and use these attributes to identify changes in lithology, porosity, and permeability. Application of the technology will reach beyond the immediate study area and affect all plays in which one must identify lateral changes in stratigraphy and lithofacies. Successful application of the technology across multiple basins in the United States could result in the addition of substantial domestic reserves.
Successful implementation of this technology will impact the following additional economic areas:
- Increased per-well and per-field production.
- Reduced drilling and exploration costs owing to fewer dry holes.
- Reduced development cost and risk.
- More-efficient operations owing to better identification of reservoirs.
- Increased identification and ultimate recovery of undiscovered resources.
- Increased exploration activity within domestic basins.
To date, the exploration risk for Mission Canyon traps has been too high to warrant a consistent level of exploration activity. Conventional 2-D and 3-D seismic data have failed to solve the stratigraphic complexities of the reservoir, and there are limited subsurface data along the trend. The failure of conventional seismic is due to the compressional velocity of the reservoir facies being too similar to the non-reservoir facies and therefore indistinguishable.
The project has achieved these milestones:
- Seismic acquisition is complete, using a spread of the largest number of active multicomponent geophones in history.
- Processing is complete, with data quality being fair to good.
- Pseudo-sonic logs have been developed for each well within the survey.
- A dipole sonic log has been acquired in a nearby well.
- A prestack multicomponent joint inversion has been performed on the dataset which has identified the productive interval of the Mission Canyon.
- A well has been drilled to test an interpretation of the multicomponent data for open fractures in the Bakken formation.
Current Status (January 2009)
The final interpretation of the Mission Canyon was completed in 2006 and a secondary interpretation of open fractures in the Bakken formation was also completed in 2006, and a well was drilled in November, 2007 to test the prediction of open fractures in the Bakken formation. Vecta reports that a 3500-foot lateral well was drilled, in the Bakken Formation in North Dakota, to test fracture predictions made using Vecta's shear-wave splitting analysis of a 9-component seismic data set. The well was swabbed and tested, but no significant oil or gas shows have been reported. It may be that fractures are present, but contain water rather than oil or gas. Drilling results will be incorporated in the final report. The project ended 2/5/2008 and DOE is awaiting the project's preliminary final report.
This project was selected in response to DOE’s Oil Exploration and Production solicitation DE-PS26-02NT15376 (September 2002).
Project Start: February 6, 2003
Project End: February 5, 2008
Anticipated DOE Contribution: $1,199,997
Performer Contribution: $3,364,754 (74 percent of total)
NETL – William Fincham (firstname.lastname@example.org or 304-285-4268)
Performer - John Beecherl (email@example.com or 214-357-0333) ext. 144
Semi-annual reports submitted to DOE on August 2003, February 2004, August 2004, February 2005, August 2005, February 2006, August 2006, February 2007, August 2007.
Vibratory equipment used as a seismic source during the field acquisition.
Processed compression data next to the time-shifted horizontal shear (SH) data demonstrating their correlative horizons.