Conclusions

Normal moveout mapping is an example of a geophysical operator which is central to many and diverse research projects, and which may have enhanced or diminished suitability for a given task depending upon various implementation details. A convenient code for such an operator should be easily reusable, in easily configurable form; antialiasing, push vs. pull, constant vs. stacking vs. interval velocity, etc. should be selectable by the researcher with trivial code modification. We implement such a moveout operator in this paper.

Over half of the reproducible figures in Basic Earth Imaging Claerbout (1995b) belong to the extended definition of an NMO-type operator. We were able to reproduce almost all of them with a single NMO subroutine. Introducing the SEPF90 data structure brings this subroutine to the world of irregular 3-D geometries. We hope to see useful applications of it in 3-D processing (and inversion) projects.