Effect of vibroseis arrays on ground vibrations: A numerical study

Vibroseis trucks are commonly used for the acquisition of seismic reflection data for petroleum exploration because they produce low levels of ground vibration. When operating in an urban setting, vibrations are typically monitored using particle velocity meters at the ground surface, and vibration measurements are quantified in terms of peak particle velocity (PPV). Distance from the Vibroseis trucks is generally used as a parameter to identify potential points of high PPV. However, numerical modeling of PPV fields surrounding multiple-truck Vibroseis arrays reveals the presence of complex zones of constructive interference where PPV can double within as little as 3 m (10 ft). Vibroseis sweep direction and duration is shown to have little effect on PPV. The results presented herein are specific to a certain set of modeling parameters, but nevertheless demonstrate that it may be necessary to perform pre-survey numerical simulation of surface vibrations to identify points relative to the Vibroseis array that are susceptible to high vibration levels, and monitor vibrations at those points.