Multi-Focusing imaging and regularization of an irregular 3D dataset in an urban environment

Nicole Elhaj, Steven Rutherford, Dan Gish, Marianne Rauch-Davies, Danil Pelman and Kostya Deev present a technique that provides coherent stacking of seismic data and enhanced pre-stack gathers. Increasing the fold for a coherent summation of the traces reduces random noise and increases the signal-to-noise ratio. The Multi-Focusing (MF) technology is based on multi-parameter and the correction formula is accurate, even for heterogeneous subsurface and strongly curved reflectors. A multi-parameter approximation for the actual traveltime surfaces, three parameters in 2D and eight parameters in the 3D case, are being utilized. These parameters are connected to emergence angles for the normal waves and radii of curvature for fundamental wavefronts, namely normal incident point and normal waves. When stacking reflection events with a larger number of seismic traces that can span many CMP gathers, the signal-to-noise ratio is enhanced and by simultaneously scanning for the parameters, negative effects are avoided and artifacts minimized.