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6.0 MAG QUAKE ROCKS CA, NV... DEVELOPING...
Magnitude Mw 6.0
Region CENTRAL CALIFORNIA
Date time 2021-07-08 22:49:49.1 UTC
Location 38.51 N ; 119.52 W
Depth 10 km
Distances 116 km SSE of Reno, United States / pop: 241,000 / local time: 15:49:49.1 2021-07-08
34 km SSW of Smith Valley, United States / pop: 1,600 / local time: 15:49:49.1 2021-07-08
10:30 p.m.: A 4.5 magnitude aftershock hit the area of Walker in Mono County Thursday evening. The town sits near the epicenter of the magnitude 6.0 quake that rattled the central and northern California region just hours earlier.
The owner of the Walker Flea Market said the area was hit with around eight or nine aftershocks throughout the evening.
Just felt another aftershock in Walker, CA. Recorded as a 4.5m. @CBSSacramento
— Laura Haefeli (@LauraHaefeli) July 9, 2021
6:07 p.m.: The USGS said in a briefing Thursday that this now 6.0-magnitude quake was particularly uncommon for the area and poses a 6% chance that this is a foreshock of a larger quake.
The agency said there hasn’t been a great deal of damage reported, but shaking could be felt from the San Francisco Bay Area to the east of Carson City Nevada. The most damage accounted for so far was the Coleville rockslide.
According to the USGS, this was the largest quake in the region since a 6.1-magnitude quake in 1994. At least 40 aftershocks have been recorded so far.
5:24 p.m.: Victoria, a woman from Walker, California reports items falling off the shelves during the quake. She estimates thousands of dollars in damage.
5:10 p.m.: A portion of Highway 395 has been closed due to rock slide concerns. The Mono County Sheriff’s Office issued this statement:
“Things are shaking in Walker and Coleville! That 5.9 earthquake and several aftershocks have caused a rockslide on 395 at Chris Flat in Walker Canyon. No other reports of significant damage yet. It was felt throughout Mono County and beyond. And no, we don’t know why it was labeled as 23 miles from Smith Valley.”
SACRAMENTO (CBS13) – One earthquake and several aftershocks could be felt across Northern California on Thursday afternoon.
The US Geological Survey reports that a 5.9-magnitude earthquake happened on the eastern side of the Sierra in California, 19 miles SSW of Smith Valley, Nevada.
There were also more than a dozen aftershocks ranging from 3.1 up to 4.2, which were near the towns of Walker, Markleeville, Dardanelle, and Coleville. They all happened just within minutes of each other.
An earthquake jolted Central California on Thursday afternoon, shaking up residents of the Sierra Nevada foothills and the San Joaquin and Sacramento valleys.
The shaking struck at 3:49 p.m., revised to a magnitude 6.0, and was centered in the Little Antelope Valley about four miles south of Coleville in Mono County, about 150 miles east of Sacramento.
Seismologists dubbed it the Antelope Valley earthquake, during a 5:30 p.m. briefing.
As of 7 a.m. Friday, more than 100 aftershocks have struck, including temblors as strong as 5.2 and 4.6, have shaken the area near the epicenter, according to the U.S. Geological Survey.
“It’s a region with known active faults,” USGS researcher Austin Elliott said, referring to the remote area on the back side of the Sierra. “This is a classic place geologists go to study.” There have been about two-dozen earthquakes of this magnitude in the region in the past 50 years; Thursday’s was the largest in the vicinity since a 6.1 quake in 1994.
Dozens of people across California — in Sacramento to as far south as Los Angeles, north to the Oregon border, the Bay Area and beyond — reported feeling the quake to the U.S. Geological Survey. By 7 p.m., over 23,000 self-reported responses were given to the federal agency’s website.
“A M~6 quake is usually felt for more than 100 miles so it is not surprising it was felt in the Central Valley,” wrote seismologist Dr. Lucy Jones in a series of posts on Twitter.
Jones wrote the quake is unlikely to have caused much damage, noting the nearest town, Smith Valley, is 20 miles from the epicenter.
“The M5.9 this afternoon is a classic normal faulting earthquake for eastern California,” Jones wrote. “As is common in this region, there are a lot of aftershocks - 10 above M3 in the first hour.”
The M5.9 this afternoon is a classic normal faulting earthquake for eastern California. As is common in this region, there are a lot of aftershocks - 10 above M3 in the first hour.https://t.co/b4WBvbM00x pic.twitter.com/8bwslx5pxj
“While there are no preliminary reports of damage or injuries, this is a rapidly evolving situation & more details will emerge in the coming hours,” the Governor’s Office of Emergency Services said on social media. “We are working closely with local officials to ensure they have the resources and support to rapidly respond to these earthquakes.”
Preliminary reports indicated two earthquakes had struck 25 seconds but 100 miles apart — but the U.S. Geological Survey revised the shaking and removed the report of a magnitude 4.8 quake in in San Joaquin County.
Elliott and other seismologists said the glitch is not uncommon as seismic waves cause reflections as they propagate. One of those reflections just happened to center in the community of Farmington, about five miles southeast of Stockton.
Elliott said the mistake happened because “our instrumentation is sparse (in areas) away from the large population centers,” and once officials reviewed the data, they updated it along with the magnitude of the actual quake.
HOW THE QUAKE FELT NEAR THE EPICENTER
In Mono County, close to the Nevada state line and the location of earthquake swarm, workers at the Bridgeport General Store and Deli froze in place when they felt the shaking, cashier Pawahnee Minder said.
“The whole store was just shaking,” she said, adding that some decks of playing cards fell to the floor but that there was no other damage.
“It lasted a good minute, maybe two. We’ve had little ones before but this was the hardest one I’ve ever experienced,” said Minder, a 20-year-old who has lived in the two roughly 85 miles southeast of Lake Tahoe her whole life.
Mono County Sheriff Ingrid Braun, said she was in her office in Bridgeport when the quake hit.
“My office rocked and rolled. It reminded me of the Northridge earthquake,” said Braun, a native of Los Angeles.
While earthquakes aren’t unusual in Mono, “this one kept growing,” Braun said. “Hella-earthquake.”
She said the only significant damage appeared to be a rock slide on Highway 395, the main route through the county, in an area called Walker Canyon. The area is mostly campgrounds and there were no immediate reports of injuries.
The highway reopened about an hour after the initial quake closed the 40-mile stretch from Bridgeport to the Nevada state line, Caltrans said. Officials said crews would remain on scene “in case of aftershocks.”
“Quite a day,” she added. “You get a free roller-coaster ride and everyone’s safe.”
Getting some #earthquake activity today in Northern California. Did you receive a #ShakeAlert-powered alert today? If so, send us a screenshot! @Cal_OES @CalConservation pic.twitter.com/Dx2gxzvM8L
— USGS ShakeAlert (@USGS_ShakeAlert) July 8, 2021
WHERE WAS THE QUAKE FELT?
Shaking was felt widely in the greater Sacramento region, as well as in Stockton and Nevada City. The shaking was also felt in the Bay Area, according to KRON-TV, which reported feeling “light shaking” in its San Francisco studio.
“It’s a pretty big aftershock series,” said Lind Gee, a geophysicist with the USGS. She said it’s typical for aftershocks to follow a quake of such magnitude.
She added that quakes are fairly common in the area near the California-Nevada border. “We have good-sized events in eastern California,” she said.
Twitter users throughout the Sacramento region reported feeling the shaking, with swimming pool water waving and one resident posting video of their ceiling lights still swaying.
Former Sheriff John McGinness was on the air for his KFBK-FM radio show when he felt the shaking.
“Geez, I was on the air,” McGinness said. “I tried to be poised and say, ‘I’m feeling something here.’
“This one went on longer than others, so I’m actually taking calls on the recall election and I started taking them on the earthquake, asking, ‘Did you feel that?’ It’s probably the longest I’ve ever experienced. I’ve felt stronger, but not longer.”
Momna Shahbaz was in the middle of a video conference meeting when she and her co-workers first began to feel shaking. After pausing and confirming with each other that they were feeling an earthquake, they decided to immediately end the call.
Shahbaz, along with her parents and siblings, went out the backyard of their Natomas home to ride out the quake.
“My sister had to leave her Zoom class, too,” she said.
The shaking was pronounced at the seat of state government, said state Sen. Mike McGuire, D-Healdsburg: “That was a heckuva earthquake to hit the Capitol.
‘NEVER FELT A QUAKE THAT STRONG IN SACRAMENTO’
Nicole Evans, a public relations executive in Fair Oaks, said she felt the shaking “big time. I have one of those ergonomic office chairs that has mesh, and my chair started bouncing.” She added that “it felt like it went on a good 60 seconds. But I didn’t know if it was my heart racing, to be honest.”
Nancy Vogel, deputy secretary for water at the California Natural Resources Agency at 1416 Ninth St. in downtown Sacramento, said she was on the 13th floor when the building began swaying.
“Our building emptied and people are milling around out front,” she said. “I never felt a quake that strong in Sacramento.”
Mary Lee Knecht, a U.S. Bureau of Reclamation official who lives in Land Park, said she was in her basement and “it felt like the ceiling was going to come down on me.”
Knecht said a friend in Curtis Park reported that “a table was shaking and things were falling off shelves.” Knecht said it was the first time she’s felt a quake in Sacramento in the 21 years she’s lived here.
WHAT MADE SACRAMENTO SHAKE? STATE GEOLOGIST WEIGHS IN
The shaking appeared to many Sacramento residents to be stronger and last longer than others in past years, but the quake was not unusual, said Steve Bohlen, California’s acting state geologist.
Bohlen said the quake’s depth played a role in how widely it was felt.
“Earthquake energy is focused and dissipated by the geology of the local area as well as the area in which it occurs,” he told The Bee. “So it is possible, even likely, that given the location of the earthquake and the geology between its origin and Sacramento it just happened to focus the earthquake energy in a way that it was felt more strongly in the Sacramento area than it it might have otherwise.”
During a briefing, USGS researcher Elliott said it wasn’t surprising that the quake made its presence known across such a wide expanse. “It was a fairly large earthquake,” he said. “Another factor was that it was 3:30 in the afternoon. People were awake, attentive.”
Magnitude measures the energy released at the source of the earthquake, the U.S. Geological Survey says. It replaces the old Richter scale.
Quakes between 2.5 and 5.4 magnitude are often felt but rarely cause much damage, according to Michigan Tech.
Jones also noted that erroneous early reports of a nearly simultaneous earthquake in the San Joaquin Valley were quickly removed by the U.S. Geological Survey.
“Automatic systems that locate quakes sometimes get confused, especially if there are very nearby few stations,” Jones wrote.
Jones wrote that earthquakes can sometimes be followed by even larger aftershocks, but said there’s only a “few percent chance” of that happening. She wrote there’s a 90% chance that the 6-magnitude earthquake will be the largest.
What is life?
It is the flash of a firefly in the night, the breath of a buffalo in the wintertime. It is the little shadow which runs across the grass and loses itself in the sunset.
With deepest respect ~ Aloha & Mahalo, Carol