Monday, February 24, 2020, 12:15PM - 1:15PM
SEEC S228 (Sievers Room)
Coffee and cookies at 11:45, as usual.
The edges of certain kinds of mountain ranges often display steep, outward-facing slopes, which are called "facets" because they look a bit like the facets on a gem stone. Geologists have speculated that the slope angle and other properties of facets might contain useful clues about the frequency of earthquakes along the mountain front. Reading these clues requires an understanding of how facets form over time by a combination of tectonic uplift during earthquakes, and erosional processes in between earthquakes. Here we use a combination of digital terrain data and numerical modeling to address the question: can the observed range of facet forms, with varying shapes, slope angles, and degree of rock exposure, be explained as a simple consequence of uplift, gradual rock weathering, and progressive downhill movement of soil? The results show that these processes, as encoded by rules in the simulation, can account for much of the diversity in facet properties. The results also support the hypothesis that facets tend to be steeper where earthquakes are more frequent, all else being equal.
Free and open to the public.