On the effects of acquisition sampling on Marchenko-based focusing and primary estimation

The Marchenko methods can retrieve both Green's functions and focusing functions from single-sided reflection data and an initial focusing function. Recent studies also show that they can be applied to eliminating multiples directly from reflection data without requiring model information as the input. In this work, we study the effect of limited acquisition sampling on both the output focusing functions and the primary estimation results obtained from Marchenko methods. For focusing functions output from the coupled Marchenko system, downsampling in either source or receiver leads to absolute amplitude errors, with the addition of spatial aliasing brought by receiver subsampling. For the projected Marchenko system used in primary estimation, downsampling in these two dimensions can completely contaminate output primaries with multiples, with similar spatial gaps brought by receiver downsampling. Therefore, the acquisition geometry has a significant impact on results of the Marchenko methods, which must be taken into account in realistic acquisition scenarios.