Residents of the Inland Empire experienced a shake-up on Saturday morning as two earthquakes struck the Ontario area within half an hour, according to reports from NBC Los Angeles. The first tremor, registering at 3.5 on the Richter scale, occurred around 10:05 a.m. about three miles southeast of Ontario. The follow-up at 10:34 A.M. measured slightly stronger at 3.9 magnitude and occurred roughly in the same vicinity.
There were no immediate reports of injuries or structural damage following the quakes, and citizens from Chino to Pasadena reported feeling the tremors, LAist sent a shake alert message and pointed out that seismologists suggest a roughly 5% chance that a more substantial quake could potentially occur soon after, although if such an event were to happen, it is more likely to be only marginally stronger. The region has been experiencing a series of smaller quakes with several aftershocks less than 2.5 in magnitude continuing to rattle the area following the initial events.
As Californians are no strangers to seismic activity, KTLA 5 News reminds residents of the recommended safety protocol during an earthquake—drop to hands and knees, cover head and neck with one arm and take shelter under a sturdy table or desk if possible, and hold on firmly to the shelter until the shaking subsides.
According to seismologist Dr. Lucy Jones, the series of tremors amounts to a small swarm occurring along the Fontana Seismicity Lineation, with Saturday's quake being the largest in that specific area of San Bernardino County since another 3.9-magnitude earthquake in 1953, as detailed by a post on CBS Los Angeles. Jones also shared that this kind of clustering is common in Southern California, which has seen its most active seismic period since 1988 earlier this summer, and while the recent tremors have been relatively moderate, the concern of more significant seismic events looms among experts and public alike.
