  Traditional free vibration-based forward models generate theoretical
dispersion curves under the assumption of planar waves, neglecting the
influence of the actual source-receiver configuration. While 2D/3D numerical
wavefield modeling approaches mimic real-field scenarios with source-receiver
information, they suffer from computational inefficiency. This study introduces
a semi-analytical wavefield modeling approach incorporating source-receiver
data acquisition layouts. The method considers a cylindrically spreading
wavefield described by the Hankel function instead of the planer wave
assumption. The approach considers both propagating waves characterized by real
wavenumbers and decaying waves with complex wavenumbers, allowing for
calculating surface displacements in both the far and near fields. The proposed
model captures the complete wavefield, including source-offset effects and
leaky waves, while maintaining computational efficiency comparable to any free
vibration-based approaches. The method entails solving the eigenvalue problem
constructed through the higher-order thin-layer method. Subsequently, it
calculates the frequency domain vertical and radial surface responses at any
desired location in space generated by a vertically positioned active source.
The overall performance of the proposed method is investigated on diverse
profiles, including regularly dispersive media, low-velocity layer models, and
thin plate structures. The vertical and radial component dispersion images are
validated against the numerical approach. The proposed method is at least two
orders of magnitude faster than the numerical method. Notably, it captures the
smooth transition of modal energy from the fundamental mode to higher modes,
occurring due to modal osculation at low frequencies. The present approach
offers a valuable tool to enhance the efficiency of active surface wave
methods.
