Lab manual provides students with practical guide to seismic processing

The latest EAGE publication - A Lab Manual of Seismic Reflection Processing by Roger A. Young, associate professor, School of Geology and Geophysics, University of Oklahoma - is a new teaching tool for university level geophysics students being launched at EAGE Paris 2004. Designed to be a practical, computer-oriented guide, the manual has been produced in close association with software development company Parallel Geoscience Corporation. Here, Prof Young introduces some of the thinking behind the project. The purpose of the Lab Manual is to serve as an extension to an introductory college-level lecture course on seismic reflection processing. In my experience, the theory from such a course is much better appreciated by students after they have had an opportunity themselves to apply seismic processing to a high-quality data set. As an instructor of upper-division university undergraduates, I have found that hands-on processing exercises expand the students’ understanding of the consequences of model simplifications and mathematical assumptions imposed on the real earth in order to make it more tractable. The material in the Lab Manual is designed to take up approximately 12 afternoon lab sessions, supplemented by brief introductions to each processing topic, the references to software documentation, and to subject references. It is intended to be a self-contained package suitable for individual use or for group use in a supervised lab setting. The data provided with the Lab Manual comes from a segment of a near-surface line shot for engineering purposes by the Geological Survey of Canada (GSC), and I am grateful to Sue Pullan of the GSC for making a portion of the Casselman survey, Line 1, available and for providing an explanation of the geological objective of the survey. The data is characterized by a high signal/noise ratio, reflection frequencies up to 350 Hz, short records, and low fold. Because it contains multiples, statics variation, and diffractions, proper processing makes an obvious improvement in image quality. It is a suitable analogue for much larger energy industry surveys. A feature of the Lab Manual is the use of the Seismic Processing Workshop (SPW) software of Parallel Geoscience Corporation. Because the flow for each SPW processing stage takes less than two minutes’ execution time on a 200 MHz PC, the dataset is ideal for either self-instruction or interactive teaching. The software package allows students to process the near-surface, 2D, reflection dataset from Canada. The processing objective is to obtain optimal vertical resolution of shallow stratigraphy overlying a bedrock reflector at a depth of approximately 50 m. The data was shot for geotechnical engineering reasons, but its wide bandwidth (600 Hz), high S/N ratio, and the presence of diffractions, multiples, and a number of strong reflections make it an ideal analogue for processing seismic profiles over shallow oil and gas targets, too.