Histograms of the Kirchhoff migration operator
James M. Close, John C. Bancroft
A new method of Kirchhoff migration is examined which utilizes a histogram to isolate for amplitude coherency along each diffraction shape. A histogram of amplitude frequencies is used to eliminate non-coherent and small amplitude data from the final migration summation. The method explored is data driven as opposed to model driven, which allows the definition of a space varying migration aperture without the need for a preconceived model. In this method, a histogram is formed of the frequency of amplitudes along each diffraction shape defined by Kirchhoff migration. It was found that if a constant amplitude scale is applied to our histogram, similar results are produced by applying an energy threshold mute to the data. It was also found that varying the histogram amplitude scale, according to the maximum energy on each diffraction shape, biased small amplitude data which aliased the migration output. It was concluded that this method works well for eliminating noise and spikes in the data while preserving dipping events, diffraction events, and flat events, which could have practical application for examining spiky seismic data.