Study finds record pressure on 2 major Southern California faults
Researchers highlight Cajon Pass as a possible link between the San Andreas and San Jacinto faults in a major quake.
A new study from the University of Hawaii at Manoa found that tectonic stress on two major Southern California faults—the San Andreas Fault and the San Jacinto Fault—is now equal to or even above levels seen at any point in the past 1,000 years. The research, published in the Journal of Geophysical Research: Solid Earth, combined physics-based simulations with earthquake records dating back about 1,000 years. Its main focus was Cajon Pass, a geologic junction that could either stop or connect rupture propagation across both fault systems. If the rupture connects, the effects could spread into dense areas such as Greater Los Angeles, San Bernardino, Riverside and Coachella Valley. The researchers stressed that the findings are not a forecast of when an earthquake will happen, but a picture of long-term stress buildup; USGS also says earthquakes cannot be predicted with certainty.