SCAIM Seminar: Tristan Van Leeuwen

I consider the inference of subsurface medium parameters from measurements of (acoustic) seismic waves. The source of such waves may be either man-made --as is the case in oil&gas exploration -- or natural -- as in global seismology. Naturally, this problem may be posed as a PDE-constrained least-squares problem. However, due to the severe non-linearity of the problem, the least-squares objective typically exhibits local minima and has a small basin of attraction. This has long been known in the seismic community and alternative solution strategies have been proposed.

I will give an intuitive explanation of why the least-squares formulation is not optimal and give a brief overview of alternative methods. This brings me to my own line of research where I seek define an alternative objective functional that has a larger basin of attraction.