tagged w/ faults
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CNN...
Work halted at 4 more Ohio fluid-injection wells in wake of quake
From Maggie Schneider, CNN
updated 6:18 PM EST, Sun January 1, 2012
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Officials have shut down fluid-injection wells in eastern Ohio in the aftermath of heightened seismic activity in the area.
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STORY HIGHLIGHTS
Ohio officials order the closure of four fluid-injection wells near Youngstown
This comes amid a probe looking at links between "fracking" and recent quakes
"We need to get more information," an official says of any possible connection
A magnitude 4.0 quake struck Saturday, one of 11 to occur in the past year
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(CNN) -- Work has been halted at four more fluid-injection wells in eastern Ohio in the aftermath of heightened seismic activity in the area, a state official said.
Ohio Department of Natural Resources Director James Zehringer had announced on Friday that one such well -- which injects "fluid deep underground into porous rock formations, such as sandstone or limestone, or into or below the shallow soil layer," the U.S. Environmental Protection Agency explains -- was closed after a series of small earthquakes in and around Youngstown.
Then on Saturday, a magnitude 4.0 earthquake struck that released at least 40 times more energy than any of the previous 10 or more tremors that had rattled the region in 2011.
Andy Ware, deputy director of Ohio's natural resources department, told CNN on Sunday that Zehringer and Gov. John Kasich subsequently have ordered the closure of four other nearby injection wells as well.
The decision comes as authorities investigate a possible link between the earthquakes and hydraulic fracturing, better known as fracking. That controversial drilling technology involves injecting water, sand and chemicals deep into the ground at high pressure to crack the shale and allow the oil or gas to flow.
Last Friday's order affecting the first well in Youngstown came six days after a magnitude 2.5 earthquake that struck that area around 1:24 a.m. on December 24. After Saturday's larger earthquake, scientists recommended that operations stop at all wells within a 5-mile radius of that original site.
"We need to get more information," Ware said.
The epicenter for Saturday's tremor was 5 miles northwest of Youngstown, 6 miles southeast of Warren and 55 miles east-southeast of Cleveland, the U.S. Geological Survey reported. According to the preliminary estimate, the earthquake struck 1.4 miles deep.
There was a lot of shaking "and a rumbling sound," said Jimmy Hughes, a former Youngstown police chief running for sheriff of Mahoning County. "I could see the house move. ... It seemed like the ground was moving. "
Ohio is far from the edges of Earth's major tectonic plates, with the nearest ones in the Atlantic Ocean and the Caribbean Sea, the U.S. Geological Survey explains on its website. Still, there are many known faults in this region, with the federal agency noting that it is likely there are additional "smaller or deeply buried" ones that haven't been detected.
While earthquakes are not unprecedented in the area, the rate of them in the past year has been unusual. That fact led Zehringer, the Ohio department head, to act late last week.
"While conclusive evidence cannot link the seismic activity to the well, Zehringer has adopted an approach requiring prudence and caution regarding the site," the natural resources department said Friday in a press release, explaining its decision to shut the first well.
Ben Lupo -- CEO of D&L Energy, an independent natural gas and oil exploration, production and marketing group that oversees the first well that was closed -- recently told CNN affiliate WKBN that there's full cooperation with experts, though he expressed grave doubts that the injection wells were to blame for the quakes.
"We have approximately 1,000 wells between Ohio and Pennsylvania and we've never had a problem ... with an earthquake or spill," Lupo said.
Dr. Won-Young Kim, one of the Columbia University experts asked by the state to examine possible connections between fracking and seismic activity, said that a problem could arise if fluid moves through the ground and affects "a weak fault, waiting to be triggered." He explained the underground waste "slowly migrates" and could cause issues miles away, adding that the danger could persist for some time as the fluid travels and seeps down toward the fault.
"In my opinion, yes," the recent spate of earthquakes around Youngstown is related to a fluid-injection well, Kim stated -- though there has been no definitive determination, by the state or other authorities, indicating as much.
There have been "moderately frequent" reports of earthquakes in northern Ohio since the first recorded one was reported in 1823, the federal agency noted. A 1986 tremor, measuring magnitude 4.8, caused some damage. Another in 1998 measured a 4.5 and was centered in northwest Pennsylvania.
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CNN's Susan Candiotti and Ross Levitt contributed to this report.
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Work halted at 4 more Ohio fluid-injection wells in wake of quake
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New Zealand quake rips new fault in earth
Officials assess at least $1.4 billion in damage, lift curfew
Image: Earthquake damage in Christchurch, New Zealand
Google; Jonas Bergler
Before-and-after images of damaged buildings on Victoria Street in Christchurch, New Zealand.
WELLINGTON, New Zealand — The powerful 7.1-magnitude earthquake that smashed buildings, cracked roads and twisted rail lines around the New Zealand city of Christchurch on Saturday also ripped a new 11-foot wide fault line in the earth's surface, officials said Sunday.
At least 500 buildings, including 90 downtown properties, have been designated as destroyed in the quake that struck at 4:35 a.m. (12:35 p.m. ET Friday) near the South Island city of 400,000 people. But most other buildings sustained only minor damage.
Only two serious injuries were reported from the quake as chimneys and walls of older buildings were reduced to rubble and crumbled to the ground. The prime minister said it was a miracle no one was killed.
Power was cut across the region, roads were blocked by debris, and gas and water supplies were disrupted, Christchurch Mayor Bob Parker said. He warned continuing aftershocks could cause masonry to fall from damaged buildings, as could gale force winds due to buffet the region Sunday.
New fault rips earth
Canterbury University geology professor Mark Quigley said what "looks to us that it could be a new fault" had ripped across the earth and pushed some surface areas up about three feet (a meter). The quake was caused by the ongoing collision between the Pacific and Australian tectonic plates, he said.
"One side of the earth has lurched to the right ... up to 11 feet (3.5 meters) and in some places been thrust up," Quigley told National Radio.
"The long linear fracture on the earth's surface does things like break apart houses, break apart roads. We went and saw two houses that were completely snapped in half by the earthquake," he said.
Roger Bates, whose dairy farm at Darfield was close to the quake's epicenter, said the new fault line had ripped up the surface across his land.
"The whole dairy farm is like the sea now, with real (soil) waves right across the dairy farm. We don't have physical holes (but) where the fault goes through it's been raised a meter or meter and a half (3 to 5 feet)," he told National Radio.
"Trouble is, I've lost two meters (6 feet) of land off my boundary," he added.
Strict building codes
Experts said the low number of injuries in the powerful quake reflects the country's strict building codes.
David Alexander / AP
People inspect a crack in the South Brighton Bridge approach in Christchurch, New Zealand, Saturday, after a powerful quake struck the region and ripped a new fault in the earth.
"New Zealand has very good building codes ... (that) mean the buildings are strong compared with, say, Haiti," which suffered widespread damage in a magnitude-7.0 quake this year, earth sciences professor Martha Savage told The Associated Press.
"It's about the same size (quake) as Haiti, but the damage is so much less. Though chimneys and some older facades came down, the structures are well built," said Savage, a professor at the School of Geography, Environment and Earth Sciences at Victoria University in the capital, Wellington.
"Thank God for earthquake strengthening 10 years ago," Anglican Dean of Christchurch, Rev. Peter Beck, told TV One News on Sunday.
Euan Smith, professor of Geophysics at Victoria University, said the fact that there "were no fatalities ... it's quite remarkable."New Zealand quake rips new fault in earth
Officials assess at least $1.4 billion in... more
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There's a hole in this possible earthquake pattern
The Mogi doughnut hypothesis, developed by a Japanese seismologist, holds that earthquakes occur in a circular pattern over decades, building up to one very large temblor in the doughnut hole.
A seismic hot spot
Photo: Signs in Parkfield, Calif., alert tourists that they are passing over the San Andreas fault. The area is so prone to earthquakes that scientists have wired it extensively to collect data. The San Andreas, along with the Elsinore and San Jacinto faults, would be enclosed in Southern California's so-called Mogi doughnut hole. Northern California’s doughnut hole includes the San Andreas and Hayward faults. (Spencer Weiner, Los Angeles Times / July 18, 2010)
PART ONE…
By Rong-Gong Lin II and Hector Becerra, Los Angeles Times
July 18, 2010
As UC Davis physicist and geologist John Rundle ponders the map of recent California earthquakes, he sees visions of a doughnut even Homer J. Simpson wouldn't like.
The doughnut is formed by pinpointing the recent quakes near Eureka, Mexicali and Palm Springs.
Seismologists call the possible pattern a Mogi doughnut. It's the outgrowth of a concept, developed in Japan, which holds that earthquakes sometimes occur in a circular pattern over decades —building up to one very large quake in the doughnut hole. Rundle and his colleagues believe that the recent quakes, combined with larger seismic events including the 1989 Loma Prieta and 1994 Northridge temblors, could be precursors to a far larger rupture.
They just don't know exactly when.
The idea of predicting earthquakes remains controversial and much debated among California's many seismologists. But as technology improves and the understanding of how earthquakes distribute energy grows, experts are gingerly offering improved "forecasts," some of which have been surprisingly prescient.
For example, Southern California was hit earlier this month by a 5.4 quake that struck in the mountains about 30 miles south of Palm Springs — several weeks after seismologists at the Jet Propulsion Laboratory and elsewhere warned that pressure was building in the San Jacinto fault zone, which is where the temblor occurred.
That forecast underscores new thinking by seismologists about how earthquakes occur.
In the past, experts paid less attention to how one fault was connected to another and how one earthquake could increase the chances of a quake on another fault. But now they believe that these connections are extremely important and that this year's temblors along the Mexican border and near Palm Springs seem to support the concept.
"Previously we would identify a fault, map it and name it," said Lisa Grant Ludwig, a UC Irvine earthquake expert. "What we've really got here is a network of faults. Maybe that's what we need to be thinking: more big-picture."
Seismologists made the forecast about the quake risk south of the Palm Springs area after seeing signs that the 7.2 Mexicali temblor in April had placed more pressure on the San Jacinto fault system, which extends from the border northwest 100 miles toward Riverside and San Bernardino. They were particularly concerned because the San Jacinto fault system connects to the massive 800-mile-long San Andreas fault, which last triggered the "Big One" in Southern California in 1857, leaving a trail of destruction from Central California to the Cajon Pass in the Inland Empire.
David Bowman, a geology professor at Cal State Fullerton, said his research indicates that the Mexicali quake — the largest to strike the region in nearly two decades — was actually triggered by a much smaller quake on a unnamed fault line. The small quake's energy "jumped on another fault and kept on going," causing the much larger Mexicali temblor that was felt all the way to Fresno.
"That fault the earthquake started on is so small, we don't even really know where it is. Yet that small earthquake — that would not have made the news at all — was able to jump onto another fault and become a magnitude 7.2 event," he said.
The big question is whether the Mexicali quake has made a destructive temblor in the L.A. area more likely. Experts see strong evidence that there is more pressure now on the San Jacinto and nearby Elsinore fault networks to the east of Los Angeles. The Elsinore fault zone is connected to the Whittier fault, which runs through densely populated sections of the L.A. area, including the San Gabriel Valley. As a result, there's a concern that a quake on the Whittier fault might be more likely.
The Mexicali quake has also turned into a treasure trove of data for earthquake experts. It comes at a time when quake technology has advanced in major ways. Sophisticated satellite images are being used to study creeping ground movement caused by tectonic pressure in advance of an earthquake.
New GPS ground monitoring equipment is tracking how far the ground has moved after a quake, allowing scientists to calculate locations of greater seismic stress. And research in the mountains west of Bakersfield, examining the tracks of earthquakes hundreds of years ago, is showing that catastrophic earthquakes — those as large as magnitude 8 — have occurred in Southern California more frequently than previously believed.
CONTINUED…There's a hole in this possible earthquake pattern
The Mogi doughnut hypothesis,... more
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