Beginning at 3:40 pm on 2 December 2011, in ENGR 110, the Department of Geosciences invites the public to the dissertation defense of Mr. Dylan Mikesell, candidate for the degree of PhD in Geophysics, working under Dr. Kasper van Wijk. Mr. Mikesell will present an oral defense of his dissertation – Subsurface characterization using head-wave artifacts in seismic interferometry. The presentation should last 45 minutes and will be followed by a short period for public questions.