Overview
- The peer‑reviewed study, which was published June 10, reconstructs about 1,000 years of fault behavior and finds stress on several segments now at or above the highest levels in the modeled millennium.
- Researchers used a physics‑based four‑dimensional model driven by radiocarbon dating, tree rings and paleoseismic records to estimate present stress and test rupture scenarios.
- The team identifies Cajon Pass as an "earthquake gate" that can either block or allow a rupture to jump from the San Jacinto system onto the San Andreas, which would greatly increase rupture length and damage.
- The study gives quantitative segment estimates, reporting roughly 3.6 MPa for the San Jacinto–Bernardino segment and about 2.8 MPa for the southern Mojave section of the San Andreas, and it warns such multi‑fault ruptures would threaten Los Angeles, San Bernardino, Riverside, Coachella Valley and key infrastructure.
- Authors stress the work does not predict when an earthquake will occur and recommend using these stress maps and scenarios to refine seismic‑hazard assessments, building standards, emergency planning and infrastructure resilience.