The complex processes involved in past changes of the Earth's climate are also at work both on the very slow, geologically long time scales, as well as on the time scales of decades to centuries, shaping our environment through natural processes and the effects of human activity. The department's environmental research includes studies of the environments in the more distant geological past, studies of the geochemical processes and geochemical cycles under natural and perturbed conditions, and analysis of the timing and driving mechanisms of the major climatic trends and ice ages. Our research into the movements of continental and oceanic plates on the Earth's surface includes field studies of their boundaries, analysis of the Earth's magnetic field through time, studies of earthquakes occuring in different geological settings, and studies of the modern and ancient sediments. Research on the Earth's interior is being conducted by laboratory experiments simulating the high pressures and temperatures at depth, theoretical studies of the composition and properties of the interior, and analysis of seismic waves travelling through the Earth. Geophysics is, literally, the physics of the Earth.
Geophysicists apply the techniques of mathematics and physics to understanding Earth processes.
Much recent research has focused on plate tectonics. Paleomagnetism, which describes the history of the Earth's magnetic field as recorded in rocks, can be used to deduce the movements of continents and oceans through time. Seismology, the study of elastic waves that travel around and through the Earth, is used to study the positions and movements of the plates on the Earth's surface. Satellite Laser Ranging and Long Baseline Radio Interferometry are new and powerful tools to measure plate motions. A vast body of knowledge based on the physics of solids and fluids bears on the studies of the history of ice sheets and of the paleoclimates.