AMPLITUDE VARIATION WITH OFFSET APPLICATION HISTORY IN MIDDLE EAST AND NORTH AFRICAN BASINS

摘要

The assumption behind Amplitude Variation with Offset (AVO) concept is that amplitude changes (either decrease or increase) with offset can be related to rock physical properties and pore-fluid content. The technique has been widely deployed in the Gulf of Mexico, and has proved to be an excellent indicator of hydrocarbons and lithology. Over the past 40 years, several studies have shown that AVO responses of gas sands differ by geologic setting. These responses have been observed in many locations around the globe, some in basins similar to the Mexican Gulf such as the North Sea, South Canada, but others are in different geological settings than the Gulf setting. In this study we review some examples from North African and Middle Eastern basins. We discuss the occurrence of AVO anomalies and the successful application of the technique for detecting and delineating hydrocarbon reservoirs. Furthermore, we illustrate case studies where the technique was used for carbonate and naturally fractured reservoirs exploration and characterization. The case histories illustrated in the study demonstrate that AVO technique is applicable in different geological settings and environments including old and deep sand reservoirs in North Africa and the Middle East. Once calibrated to the local geology. AVO can perform well even in geological conditions that differ from the Gulf of Mexico where the technique was first developed and successfully implemented.