The destructive potential of an earthquake is largely dependent on how a fault ruptures in an earthquake, making understanding the physics of rupture fundamental to assessing earthquake hazard. To better understand the physics of rupture, we must relate seismologically observable parameters such as earthquake size, radiated seismic energy, and duration of rupture to the rupture process itself.
The goal of the Physics of Earthquake Rupture project is to collect and analyze new earthquake waveform data on the San Andreas fault near Cholame, California, and to measure observable source parameters in order to better understand earthquake rupture. In particular, we focus on collecting data which allows us to differentiate the effects of tectonic environment and fault maturity (i.e. amount of cumulative fault displacement) on the earthquake rupture.
We will investigate how fault maturity and shallow fault zone structure affect rupture dynamics by (1) comparing the spatial and temporal distribution of earthquake source characteristics with those of nearby non-volcanic tremor, and (2) examining the scaling relationships of earthquake source parameters for separate event populations defined by fault maturity. We will complete a temporary deployment of 13 broadband seismometers near Cholame, California in collaboration with the University of California, Riverside.