When sea ice and rivers quake
January 20, 2015
907-474-7541
1-20-2014
Geophysicist Victor Tsai from the California Institute of Technology will give a seminar on Friday, Jan. 23, about how scientists can use seismic waves to understand rivers and sea ice.
The free lecture, part of a series sponsored by the Department of Geosciences, will begin at 3:30 p.m. in Room 201 of the Reichardt Building.
A number of physical processes, not just earthquakes and explosions, create significant ground motion, Tsai said. Ocean waves, wind, rivers and traffic all cause measurable ground displacements. Because of this, ambient seismic noise can be used to probe the nature of these processes. Tsai will discuss two ways in which seismic observations can be used to study rivers and sea ice.
Tsai also will give a brownbag seminar on Thursday, Jan. 22, on how scientists can assess the stability of the West Antarctic Ice Sheet. His talk will begin at 12:15 p.m. in the Elvey Building's Globe Room.
Tsai said the dynamics of marine-based ice sheets are of interest because of the possible catastrophic loss of ice as the sheet edge retreats in a warming climate. If scientists want to accurately predict ice sheet stability, it is crucial to understand the migration of the "grounding line" — the boundary between the part of the ice sheet that rests on the ground and the part that rests on ocean water. Tsai will discuss a better model for understanding the grounding line and, in turn, the long-term stability of the ice sheet.
Tsai is an assistant professor of geophysics at Caltech. His current projects include understanding and making use of noise correlation measurements, improving earthquake source parameterizations, creating new tomographic methods, modeling short-timescale glacier physics and modeling tsunamis.
For more information, contact Jim Beget, UAF geosciences professor, at jebeget@alaska.edu or 474-5301, or go online to www.uaf.edu/geology. A poster is available at http://www.uaf.edu/files/cnsm/geolgyflier2.pdf.