Quake Watch

LOS ANGELES (CBS) ― A magnitude-5.1 aftershock of a 1999 earthquake struck the Mojave Desert Friday night, and a second, smaller quake struck Saturday about 140 miles away from the first one.

The first quake hit at 8:18 p.m. Friday, with an epicenter 117 miles northeast of downtown Los Angeles. The epicenter was placed 35 miles east of Barstow and near Ludlow, a gas station exit on Interstate 40, according to the U.S. Geological Survey.

It was followed at 8:07 a.m. by a magnitude 3.0 quake epicentered near Olancha, a small settlement halfway between Mojave and Bishop, and about 140 miles north of Los Angeles.

It was felt in Los Angeles County, including West Los Angeles and Studio City. Calls also came in from Las Vegas, San Diego and western Arizona.

Jeremy Chestnut, 20, who works at a Dairy Queen and gas station in Ludlow, said the quake was not major.

"The ground was rolling underneath but it was very light. Nothing," Chestnut said. "I was standing in front of an ice cream machine and it makes the ground shake, too."

The quake is the second one above a magnitude-5.0 to hit Southern California this year. In July, a magnitude-5.4 quake centered in the hills east of Los Angeles was the strongest to rattle a populated area of Southern California since the 1994 Northridge disaster.

In the town of Yermo, about 20 miles from Ludlow, a dozen people in Lee's Tavern didn't seem too concerned when the bottles began to rattle.

"Everyone said, 'Oh, it's an earthquake."' said Leon Lee, the bar's owner. "We didn't hardly feel anything, just some kind of vibration."

The quake struck 16 miles northwest of Ludlow, which has a population of 10, according to the 2000 U.S. Census.

USGS geophysicist Rafael Abreu said the closest fault is the Lavic Lake Fault, in the Calico-Hidalgo fault zone, which is part of the San Andreas Fault region.

He said the movement is related to the gradual movement of the Pacific plate against the North American plate along a strike slip fault that crosses California.

The quake "is relatively shallow and if it were located in a more populated area it could be very damaging," USGS seismologist Richard Buckmaster said. "But it's out in the middle of the desert, in the middle of nowhere."

Across the Colorado River at the western Arizona border, Fort Mojave Tribal police dispatcher Jessica Hopkins said she felt a gentle rumbling.

Shaking was also felt in Las Vegas, said Scott Allison, a spokesman for the Clark County Fire Department in Nevada. He said there were no reports of injuries or damage.

"People were just calling 911 saying, 'Did I feel the earth move?"' Allison said.

The quake was just a few miles from where a 7.1-magnitude earthquake hit in 1999. USGS seismologist Lucy Jones said it was probably an aftershock of that shake. She said it's not uncommon for big earthquakes to spawn aftershocks years later.

Southern California on average feels about three moderate earthquakes a year, but the region has been unusually quiet since the Northridge quake, Jones said.

Kelly Ghiloni, a spokeswoman with the San Bernardino County Sheriff's Department in Joshua Tree, said she felt shaking for about 15 seconds but saw no major damage.

"There was some shaking, a little bit of rattling," Ghiloni said. "It was enough to wake you up and know there was an earthquake."

KCDZ-FM news director Gary Daigneault said he felt the shake in Twentynine Palms, about 70 miles south of Ludlow.

"It was a rolling motion," he said. "It was a pretty good ride."

There were no immediate reports injuries or damage.

The big quake was an aftershock of the magnitude-7.1 Hector Mine earthquake that struck on Oct. 16, 1999, according to Lucy Jones, a seismologist with the U.S. Geological Survey.

The U.S. Geological Survey's automated computers initially reported the aftershock's magnitude at 5.5, but downgraded it to 5.1 after scientists reviewed the data.

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