Abstract: Direct Hydrocarbon Indicators: Exxon's Worldwide Experience

Kurt, Rudolph; Fahmy, William; Stober, Julie- Exxon Exploration Company

Industry increasingly relies on DHI technology to identify and risk prospects in many key exploration areas, including West Africa, Gulf of Mexico, and the North Sea. As a measure of the impact of this technology, success rates are higher in plays where DHI technology can be applied (+10 to 20% for Exxon wildcats). Moreover, there is a strong correlation between wildcat success rate and the quality of anomaly support within DHI-dependent plays (60-90% success for prospects with good DHI-support vs. 10-40% for those with poor or no DHI support).

Several examples (focusing on West Africa cases) illustrate both successes and the pitfalls in DHI analysis, including:

- Preservation of seismic amplitude and phase during processing is critical. Standard industry seismic processing can create false anomalies as proven by subsequent drilling.

- Non-unique seismic response remains a fundamental limitation on our ability to predict reservoir thickness and fluid type (e.g., oil versus gas).

- 3-D AVO and visualization are powerful techniques for recognizing subtle fluid anomalies, which would otherwise be difficult to recognize.

Experience indicates that successful application of DHI technology is dependent on both optimal technologies and work processes, including:

- Calibration using physical property and modeling analysis

- Improved seismic data quality

- Integration of DHI analysis with other technologies

- Development and application of new/emerging technologies

AAPG Search and Discovery Article #90933©1998 ABGP/AAPG International Conference and Exhibition, Rio de Janeiro, Brazil