SEGJ Technical Conference

Estimation of shallow S-wave velocity structures using passive linear array observation

Abstract Microtremors were observed to estimate the near-surface 2D S-wave structure using a linear array. First, by using seismic interferometry analysis, the cross-correlation function was calculated between a reference point (far from the linear array) and the stations in the linear array. Furthermore, CMP analysis was performed by assuming the obtained cross-correlation function as a pseudo-shot gather, and then a pseudo-CMP gather at each CMP point was calculated. Then, by using the obtained pseudo-CMP gathers, the phase velocity at each CMP point was calculated by the phase-shift method. The inversion of the phase velocities at each CMP pints was performed to obtain 1D S-wave velocity structures. Finally, these structures were integrated to obtain a 2D S-wave velocity structure. It is confirmed that the obtained S-wave velocity structure shows well consistent with the model that was constructed from the CCA method.