Modeling and data-driven isolation of two-way wavefield constituents

Abstract

Synthesizing individual wavefield constituents (such as primaries, first-order scattering, and free-surface or internal multiples) is important in the development of seismic data processing algorithms, for instance, for seismic multiple removal and imaging. A range of methods that allow for the computation of such wavefield constituents exist, but they are generally restricted to relatively simple, horizontally layered media. For wave simulations on more complex models, a straightforward and performant alternative are finite-difference methods. They are, however, generally not perceived as being capable of delivering isolated wavefield constituents. Based on recent advances, we found how this can be achieved for (nonhorizontally) piecewise constant layered media. For example, we were able to accurately retrieve the isolated direct arrival of the transmission response (including tunneled waves), primary reflection data (without internal multiples), and all events related to a single (or multiple) interface(s) in a medium. Our methods required detailed knowledge of discretized medium parameters. Alternatively, if a medium is known only implicitly via recordings of reflection data, interface-related events can still be isolated through a combination of subdomain-related wavefields. We found how Marchenko redatuming can be used to derive these, which enables data-driven identification (and removal) of interface-related events from surface data.