The San Andreas Fault and San Jacinto Fault Zone have reached their highest stress levels in 1,000 years, according to a study by researchers at the University of Hawaii at Manoa, leading scientists to wonder when California’s next “Big One” will occur.

The fault lines have reached “unprecedented levels,” according to the study, which was recently published in Journal of Geophysical Research: Solid Earth. The study suggests that stress normally released in large earthquakes has continued to build as 160 years have passed since the last “major rupture.”

The study’s lead author, Liliane Burkhard, said the fault system is in a “critically loaded state.”

“Our results show that stress levels on multiple fault segments are now at or above the highest values seen in the past millennium and that the region may be capable of a large through-going rupture involving both fault systems,” Burkhard said. 

The study also found that the Cajon Pass in Southern California may act as an “earthquake gate,” which can sometimes block large earthquakes from striking along the San Andreas Fault and San Jacinto Fault Zone at the same time. However, the Cajon Pass could also “facilitate a joint rupture,” the study states. An earthquake simultaneously striking both fault lines would be “significantly more damaging” and affect highly populated areas of Los Angeles, San Bernardino, Riverside and the Coachella Valley, according to the study.

“The conditions that determine whether the ‘earthquake gate’ at Cajon Pass opens or stays closed appear to be related to how closely the stress levels on the two fault systems are aligned with each other at the time of rupture,” Burkhard said. “Right now, with stress at historically high levels across the region.”

Scientists conducted the research by feeding 1,000 years of earthquake history from the region into a computer model. The extensive history was gathered by reconstructing geological evidence through radiocarbon dating of displaced sediments and tree-ring records. 

This research can help determine earthquake threat levels and help experts plan for disasters, the University of Hawaii at Manoa said.

“This is not a prediction of when an earthquake will happen,” Burkhard said. “However, studies like this are important contributions to national and global earthquake hazard research in that we are using rigorous, quantitative science to better understand the risk facing millions of people. What we can say is that the system is critically stressed, and that physics-based models like this one give us a clearer picture of the range of scenarios we should be prepared for. That information matters for hazard assessments, infrastructure planning, and emergency preparedness.”

California residents are strongly encouraged to prepare for the next major earthquake. Earthquake preparedness tools and information are available at earthquake.ca.gov.

“If you live in or travel to areas that could be impacted by an earthquake, preparation is vital, as these events can strike suddenly, at any time, with little warning,” the state website reads.

County health officials on Monday asked the public for help identifying a woman who has been hospitalized in Los Angeles for nearly two weeks.

The unknown patient was found near Main and Winston streets in downtown Los Angeles before being brought to Los Angeles General Medical Center on June 3, according to the Los Angeles County Department of Health Services.

Hospital staff have been unable to find any family members or friends who can help identify the woman, who is believed to be between 50 and 60 years old.

She was described as having brown and gray hair and brown eyes, with no identifiable tattoos or scars. She is about 5 feet tall and weighs approximately 108 pounds.

Anyone with information is asked to contact clinical social worker Cesar Robles at 323-409-6884 or the Los Angeles General Medical Center Department of Social Work at 323-409-5253.

Two people were hospitalized Sunday night after a violent two-vehicle crash in Los Angeles’ Palms neighborhood left one victim trapped inside a mangled vehicle, authorities said.

The collision was reported around 8:34 p.m. near the 3000 block of South Tilden Avenue, according to the Los Angeles Fire Department.

Firefighters and paramedics responded to the scene and worked to free one patient who was trapped in the wreckage. The victim was successfully extricated by emergency crews.

Both patients were treated at the scene before being rushed to local hospitals, LAFD officials said.

Their conditions were not immediately available.

Video from the scene showed firefighters, paramedics, and law enforcement personnel surrounding the heavily damaged vehicles as crews secured the area and investigated the circumstances surrounding the collision.

Debris from the crash was scattered across the roadway as crews began clearing the area.

Details remain limited, and officials have not said what may have led to the crash. The incident remains under investigation.