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SWLGS Luncheon Topics

Updated January 20, 2004

Lily Boom Prospect, Ramos Field: It's Good to Have a d Plan B
LGS Continued Education
Progressive Seismic Data Mining For Reservoir Characteristics
Seismic Interpretation of Sonic Logs
Rejuvenation Using Unique Frequency Enhancement Technology
Turning Rays and Anisotropy in Prestack Time Migration
Prestack Depth Imaging in the Eastern GOM
Imaging of a Salt Face and Truncating Updip Sands...
3D Seismic Recognition Of The Jurassic Smackover Reservoir
Imaging Through Gas Clouds
The Role of Visualization in Resource Expl. & Dev.
AVO Analysis in the Middle Miocene, Central GOM
Liuhua 11-1 Field, South China Sea
Turtle Bayou - Development History
Geologic Overview of NE Miss. Fan & Delta
DeepWater AUV Experiences
Workstation Visualization Techniques
Improved AVO Crossplot Evaluation
Baldpate Field (GB 260)
4th Wave Imaging
The Seismic Well Log
Subsalt Exploration in the Deepwater Foldbelts, GOM
Seismic Attributes Past, Present, and Future

February 11, 2003
11:30 am
Lafayette Petroleum Club

Rejuvenation of a Mature Field Through Application of a Unique Frequency Enhancement Technology
Marcus L. Countiss, Pogo Producing Company, Houston, Texas


Abstract Summary: Many attempts have been made throughout the history of modern seismic to image thin beds (<1/4 of dominant wavelength) by extracting higher frequencies from seismic. In addition to simply imaging zones below normal resolution, two of the more common goals to aid in reservoir development are to define pinch-outs of producing zones and to resolve internal bed geometries. Techniques to enhance seismic frequencies are critical to achieve optimum thin bed resolution. The most common post-stack method is spectral whitening or boosting the amplitudes of all frequencies within a certain band-pass to the same level. The problem with this method is that it does not discriminate noise from signal. Noise is boosted along with the subsurface signal and, depending on the signal-to-noise ratio (SNR), whitening may fail to extract the very information we hope to resolve. Other techniques such as coherence cube technology and seismic inversion can also help define some of the thin bed properties we seek through a different approach but can still be limited by the inherent bandwidth of standard seismic. The focus here is on the application of a method that attempts to separate the signal from the noise while enhancing only the high frequency "earth signal". The technique helped to identify new well locations in thinly bedded reservoirs that would not have otherwise been drilled. More importantly, it helped to nearly quadruple daily production rates and add significant new reserves to a 27 year old Gulf of Mexico field.

Since the frequency enhancement technique was applied as a post stack process, it is desirable to have the basic processing of the dataset in state-of-the-art condition to obtain the best result. Accurate statics, velocities and migration must be applied since errors in any of these steps affect the high frequencies more so than the low frequencies. Favorable results were obtained in this example because the basic seismic data quality was good, but inferior acquisition and processing may restrict or eliminate the effectiveness of the method. Although the clear success of the drilling program supports the validity of the method, good matches with broad band synthetics demonstrate the ability of the technique to extract real high frequency signal. As with all seismic methods, there is no one "silver bullet" that will achieve all goals but this is another weapon in the seismic arsenal. The combination of multiple techniques is always the best way to improve the reliability of the prediction of a favorable result.

Biographical Sketch: Marc Countiss graduated with a B.S. in Geology with Geophysics Option from the University of Houston in 1978. He is currently District Geophysicist with Pogo Producing Company in Houston, Texas working both South Texas and offshore Gulf of Mexico. He worked for Gulf Oil E&P immediately after graduation and later Strata Energy, Inc. He spent several years as a consultant and independent prospect generator before joining Pogo in 1991. His professional interests are in exploration planning and play development, seismic sequence stratigraphy and seismic attribute analysis.