Abstract

Near-surface models are essential in identifying the optimum depth for placing the seismic explosive to acquire the seismic data and understand the weathered layer changes. Conventionally, Near-surface models were developed using the upholes acquired at defined regular intervals in the operational area. Instead of using Uphole data, microseismic data can be used to generate high-resolution near-surface models. In this study, we have analyzed three-component passive ambient noise for developing high-resolution velocity models, which could be used to understand the weathered layer (Low-velocity layer) changes and optimum depth identification at each uphole location. The Horizontal-to-vertical spectral ratio (HVSR) of the shear wave (Vs) technique uses three-component seismic noise to determine the geological interfaces at different depths. This technique can estimate the velocity variations at different interfaces with various frequency ranges of seismic noise. It creates a 1D geological/Velocity model with physical properties contrast for each depth at the acquired locations. The results at all locations were interpolated, and continuous two-dimensional velocity models were developed. The results from the present methodology compared with the conventional near-surface models have substantiated that the present methodology provides high-resolution/ reliable velocity models for interpreting the low-velocity weathered layers