California has experienced three earthquakes in the last 24 hours in an area being closely monitored for a major quake.
The US Geological Survey (USGS) detected the seismic activity along the San Andreas Fault, which spans 800 miles from Cape Mendocino in the north to the Salton Sea in the south.
Scientists warn this fault is overdue for a ‘Big One’ — a magnitude 7.8 earthquake or higher.
Friday’s earthquakes ranged from a 2.5 to 2.9 magnitude, which experts say may cause mild injuries and damages.
However, no injuries or damages have been reported as of yet.
Experts are ‘fairly confident that there could be a pretty large earthquake at some point in the next 30 years,’ Angie Lux, project scientist for Earthquake Early Warning at the Berkeley Seismology Lab, previously told DailyMail.com.
Experts predict the ‘Big One’ would cause roughly 1,800 deaths, 50,000 injuries and $200 billion in damages, according to the Great California Shakeout.
Based on historical trends, it’s estimated the San Andreas causes a major quake every 150 or so years — and the last one was 167 years ago.
California has experienced three earthquakes in the last 24 hours, sparking fears a major quake could soon strike
USGS detected the first quake, a 2.9 magnitude, Thursday afternoon, northeast of San Francisco.
This tremor was located on Calaveras Fault, a major branch of the San Andreas Fault system.
The following earthquakes hit Friday morning, one along another branch of the major fault and another directly on it.
The vast majority of earthquakes result from the constant movement of tectonic plates, which are massive, solid slabs of rock that make up the planetary surface and shift around on top of Earth’s mantle — the inner layer between the crust and core.
As the tectonic plates slowly move against each other, their edges can get stuck due to friction and stress will build along the edges.
When that stress overcomes the friction, the plates slip, causing a release of energy that travels in waves through the Earth’s crust and generates the shaking we feel at the surface.
The last major earthquakes on the San Andreas fault were in 1857 and 1906.
The Fort Tejon earthquake of 1857 was a 7.9 magnitude, which caused ground fissures in the Los Angeles, Santa Ana and Santa Clara Rivers.
USGS detected the first quake, a 2.9 magnitude, Thursday afternoon, northeast of San Francisco (pictured). This tremor was located on Calaveras Fault, a major branch of the San Andreas Fault system
Trees were uprooted, buildings were destroyed and two people were killed during the event.
The catastrophic 1906 San Francisco event was also a magnitude 7.9 earthquake, which killed 3,000 people and leveled much of the city.
Dr Sue Hough, a scientist in the USGS’ Earthquake Hazards Program, told KTLA5 that there are conflicting studies about what signs precede a major earthquake.
Some research suggested more activity happens before it hits, while others have found there is no warning, she added.
Scientists are monitoring another fault line in California, the Cascadia Subduction Zone, which they believe could also produce a powerful earthquake soon.
New research found that a 8.0 magnitude or higher quake along the Cascadia Subduction Zone, combined with rising sea levels, would cause coastal land to sink up to 6.5 feet within 30 minutes of a major tremor.
The team generated tens of thousands of earthquake models to estimate the potential range of earthquake-driven subsidence — sinking land — that can be expected from the next large Cascadia earthquake.
They determined that the most severe effects would hit southern Washington, northern Oregon and northern California, densely populated areas in the region.
This event would result in significant expansion of the coastal floodplain — an area with a one percent chance of flooding each year — increasing it from 35 square miles to 116.
If such a quake struck today, the researchers estimate that an additional 14,350 residents, 22,500 structures and 777 miles of roadway would fall within the post-earthquake floodplain, more than doubling flood exposure.
The Cascadia Subduction Zone has historically produced 8.0 or larger magnitude earthquakes every 400 to 600 years, with the last striking in 1700.
This suggests the ‘sleeping giant’ is poised for another big one soon.
