A swarm of earthquakes hit the Salton Sea Friday night, according to the U.S. Geological Survey.
The strongest temblor was initially a magnitude-4.6, but downgraded to 4.3.
The first quake of nearly 20 quakes measured a magnitude 4.0, and struck around 9:27 p.m. at a depth of less than two miles.
The others hit the same area within about 20 minutes. This was the second swarm of earthquakes to hit in a week, with the first happening last weekend about 6 miles west of Calipatria. The biggest quake recorded in that swarmed measured at a magnitude-5.3.
"It’s basically a continuation of the swarm and it picked up a little earlier this month near Calipatria, California," said USGS Geophysicist, Jana Pursley.
The sudden spurt of seismic activity isn't uncommon in the area, according to Pursley.
Salton City resident Harry Klincmann told News Channel 3 last Saturday he felt the 5.3 quake and that "it lasted about 30 seconds. Klincmann didn't feel the more recent quake.
"I felt the earthquake last night. I was pretty startled. I was in my room watching TV, and the bed starts shaking and my bed’s against the wall and the wall made a noise," said Indio resident, Jhovany Atayde. "I have a Pit Bull that started barking really loud."
Within the past 30 the USGS has reported more than 140 earthquakes with a magnitude-2.5 or larger. Within the past 24 hours of Saturday evening, that number reached more than 25 temblors.
"When you go down in magnitude this could technically be considered an aftershock or related to the initial one. The 4.3 from yesterday will have its own series of aftershocks, but they should be smaller with, perhaps based on aftershock predictions, you might have 10-15 percent chance of something equal in size or bigger," said Pursley.
Both swarms hit the Brawley Seismic Zone between the San Andreas and Imperial faults.
On Friday night seismologist Dr. Lucy Jones tweeted out, "The Brawley Seismic Zone has started up again tonight, slightly north of last Saturday's events, as though the fault extended a bit to the north. Looking back, a similar extended swarm happened in 1978. Like I said last week, they continue until they stop."
Dr. Lucy went onto say that the swarm was closer to the San Andreas fault, but was "still not in triggering range."
Though scientists say it's impossible to predict when a major earthquake will hit, residents have to be prepared for anything.
"The main part people need to realize is if there is a large earthquake, things do shake and fall off the shelves, glass tends to break. You want to make sure you have shoes handy that you can put on, some quick food to take with you, water, change of clothes, blankets, medication is important and hopefully it can take you through a few days until the emergency systems and emergency management can get things back to normal," Pursley said.