Scientists discover an earthquake gate as California faults reach their highest stress levels in 1,000 years
Key takeaways
- Earthquakes occur when stress that has accumulated in the Earth's crust is suddenly released along fractures known as faults.
- In Southern California, two of the region's most important fault systems are the San Andreas Fault and the San Jacinto Fault.
- The international research team included scientists from the University of Hawai i at M noa, the U.S.
Why this matters: new research or scientific developments with potential real-world impact.
Earthquakes occur when stress that has accumulated in the Earth's crust is suddenly released along fractures known as faults. These faults often form where massive tectonic plates move past one another but become stuck, allowing pressure to build for years or even centuries before a rupture occurs.
In Southern California, two of the region's most important fault systems are the San Andreas Fault and the San Jacinto Fault. Together, they accommodate most of the tectonic motion in the area. Northeast of Los Angeles, the two systems come close together at Cajon Pass, a geologically complex area where a rupture on one fault may be able to jump to the other. Since the magnitude 7.9 Fort Tejon earthquake struck in 1857, stress has continued to accumulate along these fault segments. That unusually long quiet period has fueled concerns among scientists about the possibility of a major future earthquake.
A new study led by Dr. Liliane Burkhard of the Division of Space Research and Planetary Sciences (WP) at the Physics Institute of the University of Bern examined 1,000 years of earthquake activity along the southern San Andreas and San Jacinto fault systems to estimate current stress levels at Cajon Pass. The international research team included scientists from the University of Hawai i at M noa, the U.S. Geological Survey Earthquake Science Center in Pasadena, and the Scripps Institution of Oceanography at UC San Diego.