A tour of Marchenko redatuming

A tour of Marchenko redatuming: Focusing the subsurface wavefield

Cui, Tianci (Schlumberger Gould Research)
Vasconcelos, Ivan (Universiteit Utrecht)
Manen, Dirk Jan Van (Institute of Geophysics)
Wapenaar, C.P.A. (TU Delft Applied Geophysics and Petrophysics)

2018-01-01

Marchenko redatuming can retrieve the impulse response to a subsurface virtual source from the single-sided surface reflection data with limited knowledge of the medium. We illustrate the concepts and practical aspects of Marchenko redatuming on a simple 1D acoustic lossless medium in which the coupled Marchenko equations are exact. Defined in a truncated version of the actual medium, the Marchenko focusing functions focus the wavefields at the virtual source location and are responsible for the subsequent retrieval of the downgoing and upgoing components of the medium's impulse response. In real seismic exploration, where we have no access to the truncated medium, we solve the coupled Marchenko equations by iterative substitution, relying on the causality relations between the focusing functions and the desired Green's functions along with an initial estimate of the downgoing focusing function. We show that the amplitude accuracy of the initial focusing function influences that of the retrieved Green's functions. During each iteration, propagating an updated focusing function into the actual medium can be approximated by explicit convolution with the broadband reflection seismic data after appropriate processing, which acts as a proxy for the true medium's reflection response.

Acoustic
Autofocusing
Internal multiples
Processing

http://resolver.tudelft.nl/uuid:3091b118-e955-4727-9127-79a34d026cd8

https://doi.org/10.1190/tle37010067a1.1

1070-485X

The Leading Edge (Tulsa), 37 (1), 67a1-67a6

Institutional Repository

journal article

© 2018 Tianci Cui, Ivan Vasconcelos, Dirk Jan Van Manen, C.P.A. Wapenaar