SRME - Reducing Prediction Cost by a Dip Angle Criteria

Abstract

Surface Related Multiple Elimination (SRME) is composed of two steps: prediction and adaptive subtraction. On the first step, we estimate the multiple contribution traces by convolving every two seismic traces that bounce on a common point at the free surface. This set of traces is called the Multiple Contribution Gather (MCG) and its size depends on the acquisition fold. The larger the fold, the larger the MCG, the more multiple data we have per single trace and hence the more costly the complexity of SRME prediction. Moreover, when using reciprocity, the MCG grows up to twice the fold size per single trace. Therefore, the complexity of SRME prediction is a crucial issue. In this paper we show how the number of traces, used for multiple prediction, can be controlled. We study the MCG from a multiple travel-time point of view which allow us to estimate the reflector angle on the MCG panel. Then, we establish a relation between regions in the MCG and the angles of reflectors from which they emerge. We show that by limiting the aperture in terms of angle, we can reduce the cost of SRME with negligible impaction on the results.