Southern California Jolted by a 4.1 Magnitude Earthquake: A Moderate Rumble

On Friday, January 5, 2024, a rooftop office building provides a view of downtown Los Angeles.Photo byRichard Vogel

A significant event rattled Los Angeles and its surrounding regions on Friday as a magnitude-4.2 earthquake struck near Lytle Creek in the San Gabriel Mountains. While this quake created a stir, causing items to shake off shelves and rocks to tumble onto Lytle Creek Road, no major damage or injuries were reported.

The epicentre of the earthquake was roughly a mile northwest of Lytle Creek, situated about 45 miles east of downtown Los Angeles, with a depth of about 5.5 miles. This seismic event follows closely on the heels of a similar magnitude 4.1 quake that occurred just days prior, during the Rose Parade in Pasadena on New Year's Day.

Residents and witnesses in the vicinity felt the impact intensely. Michael Guardado from the Lytle Creek Ranger Station recounted how the building shook vigorously, resulting in numerous rocks cascading onto the road. At Melody’s Place, a local bar, bartender Cari Torguson described a sudden jolt, causing a decorative glass item to fall and break while a jar of coffee toppled off a shelf in the store next door.

Despite its proximity to Rancho Cucamonga Quakes, a minor league baseball team, the earthquake left no major implications apart from a clever quip shared by the team on social media. The tremor, though felt as a slight rocking in downtown Los Angeles, spread its impact across several surrounding counties and cities, including Long Beach, over 50 miles away from Lytle Creek.

Seismologist Lucy Jones explained that the quake transpired in Cajon Pass, an area where the San Andreas and San Jacinto faults converge. Jones referenced a historical event, a magnitude 5.2 quake in 1970 with a foreshock measuring 4.0, which took place near the same location. This confluence of fault lines often serves as a trigger point for seismic activity in the region. Despite the unsettling nature of these earthquakes, this recent event fortunately resulted in no significant harm or destruction.