SoCal, Hawaii earthquakes

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Both Hawaii and southern California were rocked by earthquakes on Friday.

A magnitude 5.7 earthquake struck off the southern coast of the Big Island of Hawaii, according to the U.S. Geological Survey. The earthquake occurred just after 10 a.m. local time, with the epicenter located a little more than a mile southwest of the town of Pahala at a depth of nearly 23 miles.

Preliminary reports indicate that the earthquake was felt as far away as the island of Oahu, near Honolulu.

A couple of hours later, the USGS said that another earthquake occurred in the Los Angeles area, with the epicenter located about 7.5 miles northwest of Malibu.

The magnitude 4.6 quake occurred just before 2 p.m. local time at a depth of about 8.6 miles.

Local station FOX 11 reported there were no immediate reports of damage or injuries.

The deadly Feb. 9, 1971 Sylmar earthquake rattled Southern California, leaving dozens of people dead, causing more than $500 million in property damage and raised fears of a potentially devastating dam collapse.

Also known as the San Fernando earthquake, the Feb. 9, 1971, magnitude-6.5 quake struck at about 6:01 a.m. Its origin was in the foothills of the San Gabriel Mountains north of Los Angeles, but shaking was felt across a widespread part of the San Fernando Valley.

It was the most powerful in nearly four decades in Los Angeles.

Both the Veteran's Administration Hospital and Olive View Medical Center in Sylmar were severely damaged, accounting for many of the deaths. Much like the Northridge earthquake 23 years later, the quake also tore apart freeway overpasses.

But the threat of disaster didn't end when the shaking stopped. There was fear of an imminent collapse of the Van Norman Dam, which held more than 3.5 billion gallons of water just northwest of San Fernando. Part of the dam crumbled in the quake, and more damage was reported with each aftershock. Residents along the 405 Freeway were evacuated for days until the dam was shored up and determined to be safe.

The aftermath led to major changes for building construction and the Alquist-Priolo Act. The law limits construction along active faults able to rupture the ground surface.

Congress took actions that ultimately led to what is now the U.S. Geological Survey's Earthquake Hazards Program.