A series of field tests were conducted to quantify repeatability of land seismic data acquired with a surface vibrator in a desert environment. Tests conducted included six repeated 2D seismic surveys as well as daily and hourly sweep tests using buried surface geophones and buried, cemented geophones. The results indicate that in contrast to marine seismic data, even small source geometry changes (<2 m) may seriously degrade survey repeatability. In addition, even for a fixed geometry, there is significant non-repeatability caused by the interaction of the vibrator with the ground (variable coupling). Events recorded from the deeper cemented sensors exhibit significantly better repeatability compared to those from geophones buried at the surface. Unlike permanent surface piezoelectric source data, variations in travel times and amplitudes of the signals from a surface vibrator do not seem to correlate with diurnal temperature variations. It was observed that the initial sweeps acquired with a vibrator show significant time and amplitude variability as measured by both the surface and deep cemented sensors, whereas data recorded from later sweeps becomes more repeatable. It is clear that land seismic data acquired using a surface vibrator has some inherent non-repeatability, even when the source positioning errors are minimal.


Article metrics loading...

Loading full text...

Full text loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error