Southern California was struck by three earthquakes on Monday, according to data logged by the U.S. U.S. Geological Survey (USGS).
11:19 p.m. Last night, a 3.5 magnitude tremor was reported approximately 8 miles from Morongo Valley, San Bernardino County, at a depth of 4 miles.
According to USGS data, a 3.4 magnitude tremor struck San Bernardino County east of Los Angeles at 1:28 a.m. Monday, next to the town of Loma Linda. Shortly afterward, reported at 2:56 a.m., a magnitude 3.6 earthquake occurred in the Mojave Desert near the town of Ridgecrest, Kern County, initially near Little Lake.
According to ABC7, no reports of injury or damage were recorded as a result of the earthquakes. Still the two related earthquakes that happened earlier Monday morning prompted social media reactions from several California residents who said they felt the impacts.
“I was half asleep playing Sims, so I feel the earthquake now that I’m fully awake,” one Twitter user said in a tweet he liked more than 100 times.
Others have taken a relaxed attitude to warnings of tremors. “It’s strange to live in a city where regular, tiny earthquakes are common. California keeps you on your toes!” Danielle Crespo tweeted. Another user said, “You know you’re from California because ‘earthquake’ is on the trend but no one in real life has ever discussed it.”
Any California residents near the Morongo Valley quake shared their encounters with the European-Mediterranean Seismological Centre (EMSC).
“Heard it more than we felt it Very light motion, but the sound it made indicated it was originating from deep underground,” said one person located in Banning, about 13 miles southwest of the epicentre. A individual in Desert Hot Springs, 14 miles south of the epicentre, described it as a sudden shaking lasting about two seconds.”
Most of the sources suggest that the later quake in the Morongo Valley was quite tame. “One little shaking but making me know it was a quake,” said a guy about 17 miles away.
Magnitude is a measure of the magnitude of the earthquake. Experts from Michigan Tech also said that quakes between magnitude 2.5 and magnitude 5.4 are frequently felt, but generally cause only minimal damage.
In contrast, quakes between 6.1 and 6.9 may cause severe damage to inhabited areas, while quakes of more than 7.0 magnitude are considered to be major.
“The earthquake is what occurs when two blocks of the earth unexpectedly slide past each other,” says the USGS. “The surface where they slip is called the fault. The position below the surface of the earth where the earthquake occurs is called the hypocenter, and the location immediately above it on the surface of the earth is called the epicentre.”
As noted, both the San Bernardino County and the Mojave Desert are located along the San Andreas Fault, an 800-mile area known for its tumultuous tectonic action. It is the tectonic border between the Pacific Plate and the North American Plate.
According to the USGS, the biggest historical earthquakes that happened along the San Andreas fault occurred in 1857 and 1906, the latter having been estimated at magnitude 8.3, losing 700 lives and causing millions of dollars worth of damage in the province.