Multifocusing Stack - A New Time Imaging Method

The multifocusing method consists in stacking seismic data with arbitrary source-receiver distribution<br>according to a new local moveout correction. This moveout correction is based on a local spherical<br>approximation of the reflection wave front in the vicinity of an observation surface. We demonstrate that the<br>multifocusing method does not require any knowledge of the subsurface model and can produce an accurate<br>zero offset section, even in cases of a complex geological structure and low signal-to-noise ratio. The<br>estimated sets of parameters, namely the emergence angle and the wave front curvatures for the normal wave<br>and normal-incidence-point wave, which define the local moveout correction, contain important information<br>regarding the subsurface model and may be used for structural and lithological inversion. We illustrate an<br>application of the multifocusing imaging to synthetic data and compare it with conventional NMO + DMO<br>stacking, prestack time and depth migrations.