A new study suggests that Southern California’s San Andreas Fault and San Jacinto Fault Zone are experiencing their highest levels of accumulated stress in roughly 1,000 years. Researchers at the University of Hawaii at Manoa reached that conclusion in findings recently published in the Journal of Geophysical Research: Solid Earth. According to the study, stress along the fault system has reached what researchers describe as unprecedented levels. Normally, tectonic stress is released periodically through major earthquakes, but scientists say it has continued to build since the last significant rupture on these faults more than 160 years ago. Lead author Liliane Burkhard said the fault network is currently in a “critically loaded state,” meaning it may be capable of producing large seismic events. The research also examined the role of Cajon Pass, which may sometimes act as a barrier that prevents simultaneous ruptures on both fault systems. However, under certain conditions, the pass could also help facilitate a combined earthquake event.
