Asst. Professor Jonathan Aurnou
Department of Earth & Space Sciences
University of California, Los Angeles
3-4pm
Friday, January 16th, 2004
Refreshments served at 2:45pm
Munk Conference Room
Cecil and Ida M. Green Institute of Geophysics and Planetary Physics
Scripps Institution of Oceanography
University of California, San Diego
http://mahi.ucsd.edu/seminar/
Abstract:
The magnetic fields of the terrestrial planets are generated by convectively-driven dynamo processes occurring within the electrically-conductive fluid regions of planetary cores. Present experimental approaches are focusing on two complementary methods for understanding core dynamo processes: mechanically-driven dynamo experiments and buoyancy-driven convection experiments. In the mechanically-driven experiments, energy is pumped into the velocity field via impellers or pumps. Although the flows produced are not necessarily geophysically accurate, dynamo action may result, thereby producing a system of both physical and geophysical interest. In buoyancy-driven rotating magnetoconvection experiments, energy is pumped predominantly into the externally-imposed magnetic field. The buoyancy-driven flows, acted upon by strong Coriolis and Lorentz forces, are interesting analogues to core convection; the velocities, however, are far too small to generate dynamo action. Here we will review the latest mechanically-driven dynamo experiments and then discuss the results of buoyancy-driven rotating magnetoconvection experiments relevant to core convective processes.