Marchenko Multiple Elimination in a Resonant Pinch-Out Model

Abstract

The ability to separate primary reflections from multiples is important for making subsurface images. Many existing methods need some form of model information and adaptive subtraction. Marchenko methods have been modified to operate at the acquisition surface. The associated filters can be computed from the reflection response without any model information. They are a function of a freely chosen time instant that defines the time window of the filter. The scheme can be implemented without adaptive subtraction. Applying the filter to the reflection response removes all multiples from the overburden that would arrive within the time window in which the filter is defined. For this reason, the first event in the result is a primary reflection event that can be taken and stored in a new dataset containing only primary reflections. From data of a resonant wedge model with thin layers, the images after MME show that destructive interference effects are removed by MME. Reflectors are imaged that are missing in the images of the reflection response. Thin layer effects cause incomplete prediction and removal of multiples. When MME treats the combined reflections from thin layers as a single complicated event, their combined multiples from other reflectors are properly removed.