Chapter 10: AVO Anomaly Due to Tuning
A prospect with a field analog showing the same responses in amplitude, inversion, and AVO behavior was drilled unsuccessfully. In this example, the difference between the field and a prospect on the same seismic line is in the structural configuration. The field, was a flat-lying stratigraphic trap while the prospect was a stratigraphic trap formed by a wedge.
Field analog was not a structural analog, in that the producing field was essentially flat-lying and the prospect was a wedge.
Wedging geometries can produce amplitude, inversion, and AVO anomalies.
A strong analog with a producing field on the same seismic line and a number of positive hydrocarbon indicators associated with the prospect probably made this dry hole unavoidable.
Figures & Tables
A cursory look at the contents of the book might lead the reader to belive that AVO is not a successful hydrocarbon indicator, as we show many examples of AVO predictions gone awry, and dry holes drilled based on AVO anomalies. However, a closer look at the pages will give the reader the message we are trying to convey: used properly and cautiously, AVO can be a valuable tool for direct detection. The preponderance of unhappy endings in the book is unavoidable, as the goal of this book is to provide information that may prevent other dry holes being drilled. Inevitably, the best lessons are learned from mistakes, a statement that applies to life in general as well as to seismic interpretation.