California's San Francisco Bay Area will most likely face multiple devastating earthquakes in the future, as opposed to one giant earthquake, a new report suggests.
Scientists predict a 63 percent chance of another big quake before 2032, but as they brace for the "Big One" - an earthquake of magnitude 7.0 or larger expected on one of the many fault zones that snake through the region - researchers behind the study say that the area is more likely to experience a cluster of large earthquakes.
"The plates are moving," David Schwartz, a geologist with the US Geological Survey and co-author of the study, said in a press release. "The stress is re-accumulating, and all of these faults have to catch up. How are they going to catch up?"
The last time the Bay Area was devastated by an earthquake was in 1906 - a magnitude 7.9 quake that sparked a massive fire and killed 3,000 people. The study, to be released this week in the Bulletin of the Seismological Society of America, sheds light on the potential hazard of multiple quakes to the area, according to The Wall Street Journal.
"Everyone is still thinking about a repeat of the 1906 quake," Schwartz said in the press release. "But what happens if every five years we get a magnitude 6.8 or 7.2? That's not outside the realm of possibility."
Schwartz and colleagues excavated trenches across faults and put together a detailed record of all the earthquakes that have rocked the Bay Area since 1600. Between 1690 and 1776, the Bay Area's most dangerous faults unleashed a series of earthquakes between magnitude 6.6 and 7.8, they reported, occurring on five different faults. These include the Hayward fault, the San Andreas Fault, the northern Calaveras fault, the Rodgers Creek fault and the San Gregorio fault.
The Bay Area sprawls across two massive tectonic plates - the North America and Pacific plates. The plates build up friction that is released as earthquakes, Live Science reports, and most of the stress is relieved on the San Andreas Fault.
Scientists, including Schwartz, believe that as these faults struggle to catch up to the movement of the Earth's plates, it won't be long before the Bay Area is shattered again by a series of earthquakes, and the region should brace themselves for that possibility.