Introduction

Over the recent years, the continued increase in computer power backed by a sharp decrease in prices, and coupled with the advancements of computer cluster technology, have brought downward-continuation imaging methods, commonly referred to as wave-equation techniques, into the mainstream of seismic data processing SEG Workshop (2001).

Many research projects at SEP can be included in the wave-equation imaging category. All of these projects share a substantial part of their theoretical foundations, and a large part of their software infrastructure. It appears, therefore, redundant for each researcher to develop individually a substantial part of similar code.

WEI represents a Fortran90 library of programs designed for wave-equation imaging using mixed-domain (f-k,f-x) downward-continuation operators. The main goal of this library is to provide a program engine that enables the users to develop various imaging operators without having to deal with I/O or parallelization issues. Parallelization is done over frequencies using a combination of the Open MP and MPI standards. The code is modular and reusable, in the sense that the main imaging operator is divided in blocks that perform specific tasks.

This paper is a brief summary of WEI. We present some of the theoretical background as well as the main function interfaces and parameters.