9416004 Nocedal This Americas Program award will support a collaborative research project between Dr. Jorge Nocedal, Northwestern University, and Dr. Susana Gomez, Universidad Nacional Autonoma de Mexico, on optimization techniques for seismic inversion problems. The researchers aim to determine various material properties of the earth, such as slowness and impedance, by using given sets of seismic data. Seismic inversion requires the solution of two optimization problems: one highly non-linear and moderately large, and another nearly quadratic and very large. A new optimization method, tailored to solve these optimization problems, will be developed and tested on 2-dimensional seismic models. Determining the properties of the earth from seismic surface data is of great practical importance. The main obstacle to the solution of the problem at present is the excessive computing time required by current optimization techniques. One of the goals of this study is to develop new techniques that will speed up the inversion process in a fully automatic manner. The current project is enhanced by the complementarity of the collaborators' expertise. Dr. Nocedal's main research has focused on the development of new optimization algorithms capable of rapidly solving very large problems, such as those arising in seismic inversion, while Dr. Gomez has experience developing new methods for global and non-differentiable optimization problems. ***
