Ray tomography: implementation, structural uncertainties and geological constraints

Thomas Beraud and Modeste Irakarama and Paul Cupillard. ( 2018 )
in: 2018 Ring Meeting, ASGA

Abstract

Seismic depth migration allows us to image the subsurface from recorded seismic data. The re- sulting depth migrated image is usually used by interpreters to build a geological model of the subsurface. Depth imaging requires a reliable velocity model. In this article, we revisit a velocity model building technique known as migration velocity analysis (MVA). At each iteration of the process, an updated velocity model is used to perform a new depth migration. The velocity model is considered sufficiently accurate when re ectors are at along an axis of a redundant parame- ter, such as offset or re ection-angle. In this paper, we present our own implementation of MVA. We find that their exist multiple acceptable different velocity models, leading to structural uncer- tainties. Finally, we investigate the ray-tomography from an implicit structural modeling problem point of view; this results in a formalism that allows us to incorporate geological constraints in the tomographic system.

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BibTeX Reference

@INPROCEEDINGS{,
    author = { Beraud, Thomas and Irakarama, Modeste and Cupillard, Paul },
     title = { Ray tomography: implementation, structural uncertainties and geological constraints },
 booktitle = { 2018 Ring Meeting },
      year = { 2018 },
 publisher = { ASGA },
  abstract = { Seismic depth migration allows us to image the subsurface from recorded seismic data. The re-
sulting depth migrated image is usually used by interpreters to build a geological model of the
subsurface. Depth imaging requires a reliable velocity model. In this article, we revisit a velocity
model building technique known as migration velocity analysis (MVA). At each iteration of the
process, an updated velocity model is used to perform a new depth migration. The velocity model
is considered sufficiently accurate when re
ectors are 
at along an axis of a redundant parame-
ter, such as offset or re
ection-angle. In this paper, we present our own implementation of MVA.
We find that their exist multiple acceptable different velocity models, leading to structural uncer-
tainties. Finally, we investigate the ray-tomography from an implicit structural modeling problem
point of view; this results in a formalism that allows us to incorporate geological constraints in the
tomographic system. }
}