SummarySeismic data commonly suffer from time distortions attributable to surface topography and laterally changing near-surface conditions. In rough terrain areas, the near surface may include significant topographic and lateral velocity changes. In such areas conventional velocity analysis is greatly hampered by the complexity of the nearsurface. Here, we implement a multi-scale tomographic inversion approach that is based on turning rays. The inverted near-surface velocity model can be used to eradicate static and dynamic time distortions, and therefore, enhance stacking and imaging. We show the results of our work using three different 2-D real data sets.
For either 2-D or 3-D surveys, a big concern is the contamination from the near-surface, where the rough topography and laterally varying velocity and density fields can significantly distort the data in time, amplitude, and frequency content.
