The two small earthquakes that shook Los Angeles earlier this week resulted in no major damage or injuries – but there could be worse to come.
According to leading U.S. Geological Survey geophysicist Doug Given, the two quakes – a 3.2 on Monday, and a 3.5 after midnight on Friday – occurred at the intersection of two potentially critical faults that run right beneath the urban core of Los Angeles County. Both faults, claims Given, could yet trigger a powerful magnitude 7 quake.
Monday’s quake occurred near the junction of the Santa Monica faultline, which runs directly under Santa Monica Boulevard and close to Pacific Palisades, Westwood, Beverly Hills and Santa Monica. Friday’s slightly larger quake occurred along the Newport-Inglewood fault, which terminates north of Inglewood and joins the Santa Monica fault.
The notable length of each fault means they could generate a highly powerful quake, and their location beneath Westside and western L.A. County poses an obvious threat to the local population, says Given.
As well as last week’s quakes being a potential precursor to something more destructive, it’s also worth noting that one of the faults has previously triggered a hefty 6.3 quake: movement along the southern part of the Newport-Inglewood fault caused the 1933 Long Beach quake, in which 115 people died. Less seriously, in 2009, a 4.7 quake centered near Inglewood broke windows and resulted in a movie theater losing a good portion of its ceiling tiles!
A scenario generated by the Division of Mines and Geology simulated a 6.6 earthquake along the Santa Monica fault, and discovered that 54,000 buildings could be damaged – 85 beyond repair – and as many as 30 people could die, with more than 200 people hospitalized.