A shallow VSP survey was conducted in the Rothney Test Well using an EnviroVibe surface source and a downhole clamping 3C geophone in the well. The goal was to evaluate VSPs for imaging thin-bed stratigraphy in the near-surface environment. Two offset VSPs were obtained with the vibrator located 15m and 30m south of the wellhead. The vertical component data were subjected to wavefield separation to remove down-going P-wave and S-wave events, as well as other up-going and down-going low-velocity

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... events. The residual up-going P-wave reflections were mapped using a simplified VSP/CDP procedure. The reflections on the resulting reflectivity maps corresponded closely to the near-surface stratigraphy of the Paskapoo formation as identified by sonic velocity, resistivity, and natural gamma-ray logs. The project confirmed that the EnviroVibe vibrator used in near-surface VSP surveys produces enough high-frequency energy to be effective for imaging relatively thin stratigraphy in the upper 100m.