His research is directed at understanding the dynamics of volcanic explosions as they relate to the shallow conduit system as well as the deep plumbing structure of the volcano edifice. Lees pioneered investigations in seismic tomography in regional and local settings using earthquakes as sources. Professor Lees collects data on active volcanoes with students from UNC and international collaborators from around the world. He has worked extensively on exploding volcanoes in Ecuador, Galapagos, Guatemala and Chile. Lees leads field excursions to these dangerous zones, works with local researchers and disaster mitigation experts, and trains students as well as conducting basic research in the physics of volcano and earthquake activity.