Earthquake Hazards in the Santa Barbara-Ventura Area Workshop Report

Craig Nicholson, Thomas K. Rockwell, & Chen Ji

Published July 29, 2025, SCEC Contribution #15052

The 29 June 1925 M6.5 Santa Barbara earthquake was a seminal event for the city of Santa Barbara and for the perception of earthquake hazards statewide in California. The 100th anniversary offered a unique and timely opportunity to re-evaluate and better understand the likely causative fault (or faults) for this and other major damaging earthquakes in the Santa Barbara-Ventura area, as well as important aspects of the active 3D fault geometry, the significance of variable uplift, fault slip and geodetic strain rates along the coast, and the more extensive earthquake and tsunami hazards for this important active earthquake region with large urban populations at risk. As a SCEC Special Fault Study Area (SFSA), numerous wide-ranging, multi-disciplinary studies were undertaken that resulted in major conflicting interpretations that have yet to be resolved. Since the last major Ventura SFSA review, nine years of important datasets, reports and publications have been developed that need to be properly integrated and reconciled if they are to provide critical insight, data validation, and discrimination between these competing alternative fault geometry and hazard models. This science workshop and field trip brought together many of these disparate groups in the areas of 1925 and more recent earthquake history, offshore geophysics, crustal structure, seismicity, geodesy, fault modeling, tectonic geomorphology, paleoseismology, sedimentology, and dynamic rupture modeling to enable review and evaluation of the important observations and their implications for updated earthquake rupture, crustal deformation, geodetic strain and earthquake hazard models for this region.

Citation
Nicholson, C., Rockwell, T. K., & Ji, C. (2025). Earthquake Hazards in the Santa Barbara-Ventura Area Workshop Report. , : Statewide California Earthquake Center. https://www.scec.org/events/2025-santa-barbara-earthquake-workshop/