Climate-Modulated Channel Incision and Rupture History of the San Andreas Fault in the Carrizo Plain

Lisa B. Grant Ludwig, Sinan O. Akciz, Gabriela R. Noriega, Olaf Zielke, & J Ramon R. Arrowsmith

Published 2010, SCEC Contribution #1305

The spatial and temporal distribution of fault slip is a critical parameter in earthquake source models. Previous geomorphic and geologic studies of channel offset along the Carrizo section of the south-central San Andreas Fault assumed that channels form more frequently than earthquakes occur and suggested that repeated large-slip earthquakes similar to the 1857 Fort Tejon earthquake illustrate typical fault behavior. Here, we show that offset channels in the Carrizo Plain incised less frequently than they were offset by earthquakes. Channels have been offset by successive earthquakes with variable slip since ~1400. This nonuniform slip history reveals a more complex rupture history than previously assumed for the structurally simplest section of the San Andreas Fault.

Citation
Grant Ludwig, L. B., Akciz, S. O., Noriega, G. R., Zielke, O., & Arrowsmith, J. R. (2010). Climate-Modulated Channel Incision and Rupture History of the San Andreas Fault in the Carrizo Plain. Science, Science Express, online. doi: 10.1126/science.1182837.