A 4.0 magnitude earthquake was felt across many areas of San Diego County on Wednesday, Dec. 6, at 4:33 p.m.
The epicentre of the earthquake was 10 miles deep in the San Felipe Hills – about 8 miles northeast of Julian, California, which is just more than an hour's drive from downtown San Diego.
At 4:38 p.m., the USGS registered another 3.1 aftershock in the same location.
According to the USGS, the rumblings were felt in Julian, Warner Springs, Del Mar, Poway, Alpine, La Jolla, Ramona, Escondido, and El Cajon.
"It can produce large earthquakes, and might have produced the historical 1890 earthquake, which was 6.3 or close to that."
The Earthquake Valley fault is one of the most active fault lines in Southern California.
There were no reports of structural damage or injuries.
