Independence Day Earthquake Felt Throughout Westside, 6.4 preliminary measurement

An earthquake at 10:33 am PST on July 4 was felt from Santa Barbara to San Diego, and as far East as Las Vegas.

The temblor went on for over a minute. It was felt throughout the Westside of Los Angeles County as a powerful rolling motion. The quake was centered 12 KM southwest of Searles Valley California.

It registered a preliminary magnitude of 6.4 on the Richter scale, ranking it as probably the biggest southland shock in 20 years, since the 1999 Hector Mines Earthquake near 29 Palms.

However, the epicenter halfway between Los Angeles and Las Vegas lies in a relatively unpopulated area (relative to the Northridge Earthquake of 1994, centered in the San Fernando Valley). The Kern County Fire Department tweeted that it had responded to "nearly 2 dozen incidents ranging from medical assistance to structure fires in and around the city of Ridgecrest." Photos showed smashed bottles at a liquor store and a broken road in the Ridgecrest area.

Searles Valley is near Death Valley, in Eastern Southern California's Mojave Desert, Kern County. The earthquake occurred near there, at an 8.7 KM depth.

The earthquake happened during Santa Monica's annual 4th of July parade. Stilt walkers wondered why they suddenly felt off balance, and cars in the parade shook from side to side.

Authorities said they had received no reports of major damage or injuries, as of 12 noon PST. Authorities were responding to emergency calls in Ridgecrest, near the epicenter of the quake, according to the Los Angeles Times website.

Caltech seismologist Lucy Jones conducted a midday press conference in Pasadena. California's star seismologist advised people to anticipate after shocks in the coming days.

"We should be expecting lots of aftershocks," Jones said. She estimated that there was a "greater than 50-50" chance of an earthquake of magnitude 5.5 or more Thursday afternoon.