1. School of Earth and Space Sciences, Peking University, Beijing 100871, China; 2. Research Institute of Petroleum Exploration & Development, PetroChina, Beijing 100083, China
Abstract:The multi-focusing (MF) stacking method,which helps improve both signal-to-noise ratio (S/N) and resolution,has been widely used in the recent years.On one hand,the MF stacking method can solve stretching distortions for traces at far offsets with double-square-root time correction formula rather than muting,so the data integrity can be preserved.On the other hand,this method stacks traces of different CMP gathers so that the folds are increased which results in higher S/N as well as higher resolution.In this article,we review comprehensively some new developments of the MF stacking method such as planar MF,irregular MF,spherical MF,and non-hyperbolic MF,and their applications in multiple prediction,stacking signal enhancement,data regularization,and diffraction wave imaging.Moreover,we suggest a preliminary prospect of this method development in the future.
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