Geodesy

"Our group uses geodetic and other techniques to study the motions and deformation of the solid earth: plate motions, deformation due to active tectronics, earthquakes, aseismic fault slip events, and the deformation associated with active volcanoes."
Jeff Freymueller 

Ash from Okmok's 2008 eruption covers the GPS antenna, as well as the hut and solar panels that make up station OKCE, located within Okmok's caldera.