Geomorphology – Understanding the Near-surface Impact on Seismic Data

Surface seismic data are significantly affected by the properties of the near-surface strata. We propose to integrate information extracted from geomorphology into the seismic processing workflow. Topography classification of the elevation and lithology information of satellite imagery allows mapping formation tops, which in turn, provide the basis for 3D near-surface modelling. The lithology class map can be converted into a surface velocity map for the estimation of coherent noise velocities. The 3D geologic model can be converted into an elastic model using standardized velocities. The result is a model of the statics estimates, which can be generated prior to data acquisition. The comparison of the model with refraction statics from data processing reveals that the estimate matches the refraction statics in areas with homogeneous surface lithology. In terrain with heterogeneous surface lithology such as isolated limestone ridges and steep cliffs with rapidly changing lithology, differences are observed, which are yet to be explained.