Geophysicists aim to understand the dynamics of the Earth through research on the physical processes, properties, and structure of the planet on which we live. The Geophysics group at UC Davis is involved in a diverse spectrum of research activities including geodynamics, marine geophysics, seismology, paleomagnetism, geodesy, natural hazards, and tectonics. In their research, faculty and students in geophysics use theoretical modeling, computer simulations, data analyses, laboratory experimentation, and land and marine field observations.
Billen's primary research interest focuses on using numerical models to test hypotheses about the spatial and temporal variations in the physical properties of rocks within the earth. This is done by comparing predictions from numerical models to observations made at the earth's surface from geophysics (e.g. topography, tomography, strain-rates), and geochemistry (e.g. temperature and pressure of melting, water content, age of deformation) and geology. In using geodynamic models in this way, examples of how the Earth has deformed in the past provide an important guide to interpreting model results. This leads to her second research focus, plate tectonics, or more specifically, making geophysical observations which help to constrain both when and how tectonic plates have moved and deformed.
The solid Earth is in a continual state of deformation both in the deep interior as well as at its surface. Kellogg’s research area is geodynamics: understanding how convection in the Earth's mantle operates and drives geologic processes, and understanding the forces causing earthquakes and landscape change. Her group’s current projects include: computer modeling of the thermal and chemical evolution of the Earth; modeling the dynamics of mixing in the Earth's mantle; modeling and observing deformation in the crust associated with earthquakes. Other research interests include scientific visualization to explore the Earth’s surface and interior using immersive, interactive, virtual reality technology.
Rudolph's research involves geological fluid mechanics, broadly defined. Recent and ongoing projects investigate controls on flow and melting in the mantle wedge, development of large-scale mantle structure, inference of mantle viscosity structure from joint models of mantle density and seismic wavespeeds, and eruptive processes in geysers and mud volcanoes (including the devastating eruption of Lusi in East Java, Indonesia) as analogues to magmatic volcanoes.
Research is focused on understanding the dynamics of earthquakes through numerical simulations; pattern analysis of complex systems; dynamics of driven nonlinear Earth systems; and adaptation in general complex systems. Computational science and engineering is an emerging method of discovery in science and engineering that is distinct from, and complementary to, the two more traditional methods of experiment/observation and theory. The emphasis in this method is upon using the computer as a numerical laboratory to perform computational simulations to gain insight into the behavior of complex dynamical systems, to visualize complex and voluminous data sets, to perform data mining to discover hidden information within large data sets, and to assimilate data into computational simulations.
Planet formation and evolution with focus on collisional processes, including giant impacts and impact cratering. Laboratory measurements of the equation of state and rheological properties of planetary materials using shock wave techniques. Experimental and computational studies of impact processes to interpret the formation, resurfacing history, physical properties, and internal structure of planets and small bodies.
Researchers and Emeriti
McClain exploits a variety of geophysical techniques, in conjunction with geological observations, to understand the structure and evolution of the Earth's crust - examining problems using seismic refraction and earthquake data, as well as magnetic and gravity measurements. Much of his work has focussed on the mid-ocean ridges, with particular emphasis on how magma is stored and how this affects hydrothermal systems along the axis of mid-ocean ridges. UC Davis geophysicists were the first to show that ridge magma chambers must be narrow, and that hydrothermal systems are accompanied by extensive microseismicity. They are using these geophysical tools to study transform faults as well as underwater volcanoes that erupt near mid-ocean ridges. With his students, McClain has moved onto the continents, with projects in the Monterey Bay, the central California coast, and northeastern California.
Professor Turcotte has worked on a wide variety of problems in geodynamics. He has also worked on a wide variety of applications of fractals and chaos to problems in geology and geophysics. Don currently supervises graduate student research on induced seismicity and the distribution of carbon in the earth.
For much of his career, Ken Verosub has used the magnetic properties of rocks, sediments and soils to determine the behavior of the Earth's magnetic field, the ages of sedimentary sequences, the motions of tectonic plates, and the history of the Earth's climate during the past 40 million years. In addition to on-going paleomagnetic and environmental magnetic studies, he is working on volcanic eruptions that have caused global cooling, seismic risk and subsidence problems in the Sacramento-San Joaquin Delta, the identification of deep groundwater aquifers and the determination of river flows directly from geospatial imagery.