Vibroseis Harmonic From Noise to Signal - Case Study of ZVSP in a Highly Deviated Well

The Vibroseis is considered the most efficient source for land seismic acquisition for its flexibility in designing pilot sweeps. However, due to non-linearities in both the Vibroseis mechanism and the near-surface, the omitted signal is distorted by harmonics. We aim to make use of harmonics by decomposing the ground force signal in the analytic signal domain, and attenuating the low-order harmonic noise in the uncorrelated data. Our goal is to utilize these harmonics to enhance the frequency content of the acquired data, allowing for improved imaging results. We compare three datasets, that is the correlated ground force data, the correlated fundamental mode data, and the correlated first-order harmonic data from a zero-offset Vertical Seismic Profiling data acquired in a deviated well in Saudi Arabia. The results show that the frequency content of the first order harmonic data is approximately twice that of the fundamental mode data, enhancing the frequency content of the data and helping in imaging thin features.