Nearly 200Â small earthquakes â€”Â including threeÂ of a magnitude greater than 4 â€”Â struck the Salton Sea area over the last day or so.
According to the U.S. Geological Survey, the swarm of quakes started early Monday morning and continued into the evening. Quakes measuring 4.3 and 4.2 magnitude occurred Monday night. Â Nine of the quakes measure greater than 3.0.
Swarms of small to moderate earthquakes are fairly common in the area. In 2009, the Salton Sea saw a swarm of more than 200 small quakes.
The sea sits atop a very thin crust that is being constantly stretched as the North American and Pacific plates grind against each other. The area is also veined by dozens of faults â€”Â most notably the San Andreas –Â that run parallel to and crisscross one another.
Scientists believe that because of the thinness of the crust, hotter material can get closer to the surface and cause temblors.
Seismologist Lucy Jones said on Twitter on Monday night that magnitude 4 quakes near the San Andreas â€œincrease the chanceâ€ of a big quake â€œa little bit.Â But we have swarms without big [earthquakes] â€”Â most likely nothing more will happen.â€