Seismic source comparison for compressional and converted-wave generation at Spring Coulee, Alberta. Part I: Heavy vibroseis-dynamite comparison

Gabriela M. Suarez Barbero, Robert R. Stewart

A seismic line was shot in such a way that characteristics from two different seismic sources could be compared. Two 54-shot seismic datasets were created that were identical in all respects except that one used a dynamite source, while the other used two 48,000 lb vibrators. After identical processing, the final stacked sections of the dynamite and vibroseis datasets are very similar in character and temporal resolution. Examination of the P-wave raw shot records show that in terms of frequency content and signal strength, the explosive data appears superior to the vibroseis; however, the quality of the dynamite records is variable. F-x spectral analyses of the raw data and stacked sections reveal that both datasets show similar characteristics for areas corresponding to noise, data and first breaks for the raw shot gathers, and power and coherence from 10 to 40 Hz for the P-wave stacked section, and from 10 to 25 Hz for the converted-wave stacked section. From our results, we could say that in terms of data quality any of the sources could be used; however, these criteria must be judged with respect to the total cost of the project and the most appropriate source for the project budget.