Industry increasingly relies on DHI and AVO technology to identify and risk prospects in many key exploration areas, including West Africa, the 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 (+20% for ExxonMobil wildcats). A calibrated DHI rating system, using both DHI and data quality characteristics, provides a structured approach to evaluate DHI quality on a risk analysis basis. Based on analysis of over 100 anomalies drilledd with pre-drill DHI ratings, there is an excellent correlation between predicted and actual anomaly success rate within DHI-dependent plays.

Several examples from around the world illustrate both success and pitfalls in DHI/AVO analysis. Key points include:

• Preservation of seismic amplitude and phase is critical. Standard industry seismic acquisition and processing can create false anomalies and erros in quantitative predictions 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).
• 3D AVO and visualization are powerful techniques for recognizing subtle fluid anomalies, which would otherwise be difficult to recognize.

  Experience indicates that best practice 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, inlcuding pre-stack attributes
• Integration of DHI analysis with other technologies Development and application of new and emerging technologies
• Development and application of new and emerging technologies.