The Geophysics faculty are concerned with the broad range of physical processes affecting the solid Earth, from the core, mantle, and crust to the cryosphere, and carry out related studies of Mercury, Mars, and Earth's moon. We focus on understanding plate-tectonic processes in marine and terrestrial settings, determining the structure of the Earth's interior, and understanding earthquake and volcano dynamics. We study mechanisms for ice, magma, and sediment transport and for the exchange of mass between the solid Earth and its fluid envelope, and we work to understand interactions of large-scale surface deformation with the oceans and atmosphere. We are also concerned with the quantitative study of natural hazards and associated risks, hydrocarbon exploration and extraction, and explosion and earthquake monitoring for the verification of nuclear test-ban treaties. Our research draws on a variety of approaches, including seismology; geodesy; remote sensing; volcanology; physical glaciology; rock mechanics; and geophysical fluid dynamics. We emphasize the integration of data-analysis and modeling approaches, and many faculty maintain active field programs and engage in the development of geophysical instrumentation. The Geophysics faculty contribute expertise to inform decision-making at the local, national and international levels.