A New Processing and Imaging Procedure for Foothill Seismic Data

Traditional seismic processing and imaging procedures fail to work well in foothill areas. Based on analysing the complex wave propagation phenomenon and the data features of foothills, we suggest a new processing and imaging procedure for foothill seismic data, which is composed of the following key points: (1) Choosing a smoothed datum which is near the topography to remove the high wavenumber move-out. (2) Monte Carlo depth migration scanning method is used to estimate the initial background velocity. (3) Tomography based on beam ray angle gathers is used to estimate the more accurate migration velocity. (4) Beam-ray PSDM or RTM is used as the final imaging tool. This procedure focuses on velocity model building and replaces traditional static correction by near-surface velocity model building. In addition, the in-phase stacking of reflections from half Fresnel band is used to do the noise attenuation, which is very important for the effective migration velocity estimation and velocity model building.