NewsWatch: 2006: Tahoe Geology

[Narrator:] From the University of California at Davis, this is NewsWatch.

[Paul Pfotenhauer:] The geologic foundation of Lake Tahoe is important for scientists to know if they are to preserve its future.

[Ken Verosub:] We need to look at the geologic record in order to understand how Tahoe has changed through time, and in that way we can better understand what are the natural changes that we can expect in the Tahoe basin, and what are the ones that people are imposing on the Tahoe basin.

[Paul Pfotenhauer:] Scientists know that at the bottom of the lake there are large structures that look like earthquake faults.

[Ken Verosub:] We're very interested in knowing what the rate of movement is on those faults.

[Paul Pfotenhauer:] Knowing that information would tell scientists the role that earthquakes and landslides have played in shaping the basin.

[Ken Verosub:] There is a bit of controversy about how Tahoe was formed. It is not, as many people think, a big volcanic crater. It was formed by earthquake activity.

[Paul Pfotenhauer:] From the muddy bottom, deep core samples will be taken that will reveal the history of the lake one million to two million years ago. Verosub's team will study the history of the lake.

[Ken Verosub:] By looking at those magnetic properties, we can draw conclusions about the climate record in which the sediments were deposited.

[Paul Pfotenhauer:] If scientists have a better grasp of the climate history of the basin, the better prepared they will be to manage pollution changes.

[Ken Verosub:] You really can't manage the basin unless you understand what the natural variability of the climate and the sediments are at Lake Tahoe.

[Paul Pfotenhauer:] Tahoe experts know a lot about the lake in three dimensions, but what scientists would like to add is a fourth dimension, namely the dimension of time. Reporting from UC Davis, I'm Paul Pfotenhauer.

[Narrator:] For more information, please log on to broadcast.ucdavis.edu.