Marine Paleoseismic Evidence for Seismic and Aseismic Slip Along the Hayward‐Rodgers Creek Fault System in Northern San Pablo Bay

Abstract

Refining the earthquake history along the Hayward-Rodgers Creek fault zone is critical for estimating the earthquake hazard of and planning for future large earthquakes in the heavily populated San Francisco Bay area. Currently, the 30-year mean probability of a magnitude (M) > 6.7 earthquake on the combined Hayward-Rodgers Creek fault is the highest among faults in the region (Aagaard et al., 2016;Field et al., 2015). Understanding the behavior of an earthquake rupture when it encounters a fault bend requires in-depth knowledge of the fault geometry and connectivity, but also the earthquake history and the amount and distribution of creep, or aseismic slip, occurring along the fault system. Compilations of paleoseismic rupture histories along fault systems worldwide are used to characterize spatial-temporal patterns of large surface-rupturing earthquakes (e.g.,