A Closer Look At The Sixth Seal (Revelation 6:12)

A Look at the Tri-State’s Active Fault Line

Monday, March 14, 2011

By

Bob Hennelly

The Ramapo Fault is the longest fault in the Northeast that occasionally makes local headlines when minor tremors cause rock the Tri-State region.

It begins in Pennsylvania, crosses the Delaware River and continues through Hunterdon, Somerset, Morris, Passaic and Bergen counties before crossing the Hudson River near Indian Point nuclear facility.

In the past, it has generated occasional activity that generated a 2.6 magnitude quake in New Jersey’s Peakpack/Gladstone area and 3.0 magnitude quake in Mendham.

But the New Jersey-New York region is relatively seismically stable according to Dr. Dave Robinson, Professor of Geography at Rutgers. Although it does have activity.

“There is occasional seismic activity in New Jersey,” said Robinson. “There have been a few quakes locally that have been felt and done a little bit of damage over the time since colonial settlement — some chimneys knocked down in Manhattan with a quake back in the 18th century, but nothing of a significant magnitude.”

Robinson said the Ramapo has on occasion registered a measurable quake but has not caused damage: “The Ramapo fault is associated with geological activities back 200 million years ago, but it’s still a little creaky now and again,” he said.

“More recently, in the 1970s and early 1980s, earthquake risk along the Ramapo Fault received attention because of its proximity to Indian Point,” according to the New Jersey Geological Survey website.

Historically, critics of the Indian Point Nuclear facility in Westchester County, New York, did cite its proximity to the Ramapo fault line as a significant risk.

In 1884, according to the New Jersey Geological Survey website, the  Rampao Fault was blamed for a 5.5 quake that toppled chimneys in New York City and New Jersey that was felt from Maine to Virginia.

“Subsequent investigations have shown the 1884 Earthquake epicenter was actually located in Brooklyn, New York, at least 25 miles from the Ramapo Fault,” according to the New Jersey Geological Survey website.

New York Subways at the Sixth Seal (Revelation 6)

           

How vulnerable are NYC’s underwater subway tunnels to flooding?Ashley Fetters
New York City is full of peculiar phenomena—rickety fire escapes; 100-year-old subway tunnelsair conditioners propped perilously into window frames—that can strike fear into the heart of even the toughest city denizen. But should they? Every month, writer Ashley Fetters will be exploring—and debunking—these New York-specific fears, letting you know what you should actually worry about, and what anxieties you can simply let slip away.
The 25-minute subway commute from Crown Heights to the Financial District on the 2/3 line is, in my experience, a surprisingly peaceful start to the workday—save for one 3,100-foot stretch between the Clark Street and Wall Street stations, where for three minutes I sit wondering what the probability is that I will soon die a torturous, claustrophobic drowning death right here in this subway car.
The Clark Street Tunnel, opened in 1916, is one of approximately a dozen tunnels that escort MTA passengers from one borough to the next underwater—and just about all of them, with the exception of the 1989 addition of the 63rd Street F train tunnel, were constructed between 1900 and 1936.
Each day, thousands of New Yorkers venture across the East River and back again through these tubes buried deep in the riverbed, some of which are nearing or even past their 100th birthdays. Are they wrong to ponder their own mortality while picturing one of these watery catacombs suddenly springing a leak?
Mostly yes, they are, says Michael Horodniceanu, the former president of MTA Capital Construction and current principal of Urban Advisory Group. First, it’s important to remember that the subway tunnel is built under the riverbed, not just in the river—so what immediately surrounds the tunnel isn’t water but some 25 feet of soil. “There’s a lot of dirt on top of it,” Horodniceanu says. “It’s well into the bed of the bottom of the channel.”
And second, as Angus Kress Gillespie, author of Crossing Under the Hudson: The Story of the Holland and Lincoln Tunnels, points out, New York’s underwater subway tunnels are designed to withstand some leaking. And withstand it they do: Pumps placed below the floor of the tunnel, he says, are always running, always diverting water seepage into the sewers. (Horodniceanu says the amount of water these pumps divert into the sewer system each day numbers in the thousands of gallons.)
Additionally, MTA crews routinely repair the grouting and caulking, and often inject a substance into the walls that creates a waterproof membrane outside the tunnel—which keeps water out of the tunnel and relieves any water pressure acting on its walls. New tunnels, Horodniceanu points out, are even built with an outside waterproofing membrane that works like an umbrella: Water goes around it, it falls to the sides, and then it gets channeled into a pumping station and pumped out.
Of course, the classic New York nightmare scenario isn’t just a cute little trickle finding its way in. The anxiety daydream usually involves something sinister, or seismic. The good news, however, is that while an earthquake or explosion would indeed be bad for many reasons, it likely wouldn’t result in the frantic flooding horror scene that plays out in some commuters’ imaginations.
The Montague Tube, which sustained severe damage during Hurricane Sandy.
MTA New York City Transit / Marc A. Hermann
Horodniceanu assures me that tunnels built more recently are “built to withstand a seismic event.” The older tunnels, however—like, um, the Clark Street Tunnel—“were not seismically retrofitted, let me put it that way,” Horodniceanu says. “But the way they were built is in such a way that I do not believe an earthquake would affect them.” They aren’t deep enough in the ground, anyway, he says, to be too intensely affected by a seismic event. (The MTA did not respond to a request for comment.)
One of the only real threats to tunnel infrastructure, Horodniceanu adds, is extreme weather. Hurricane Sandy, for example, caused flooding in the tunnels, which “created problems with the infrastructure.” He continues, “The tunnels have to be rebuilt as a result of saltwater corroding the infrastructure.”
Still, he points out, hurricanes don’t exactly happen with no warning. So while Hurricane Sandy did cause major trauma to the tunnels, train traffic could be stopped with ample time to keep passengers out of harm’s way. In 2012, Governor Andrew Cuomo directed all the MTA’s mass transit services to shut down at 7 p.m. the night before Hurricane Sandy was expected to hit New York City.
And Gillespie, for his part, doubts even an explosion would result in sudden, dangerous flooding. A subway tunnel is not a closed system, he points out; it’s like a pipe that’s open at both ends. “The force of a blast would go forwards and backwards out the exit,” he says.
So the subway-train version of that terrifying Holland Tunnel flood scene in Sylvester Stallone’s Daylight is … unrealistic, right?
“Yeah,” Gillespie laughs. “Yeah. It is.”
Got a weird New York anxiety that you want explored? E-mail tips@curbed.com, and we may include it in a future column.

More Shaking Before the Sixth Seal: Revelation 6

For the 21st time this week, earthquakes hit the Columbia by I area

By Noah FeitUpdated July 03, 2022 12:16 PM

Two more earthquakes were confirmed in the Columbia area early Sunday morning as seismic activity continued following a recent series of relatively powerful earthquakes.

Sunday’s 1.9 and 1.6 magnitude earthquakeswere the 20th and 21st to hit the Midlands in the past week, according to the South Carolina Department of Natural Resources Geological Survey.

The first earthquake, recorded at a depth of 2.1 kilometers, or about 1.3 miles, was reported within 3 miles of Elgin at 12:16 a.m., the South Carolina Emergency Management Division said. The second hit about 2 miles beneath the surface in the area closer to Lugoff at 6:29 a.m., according to the U.S. Geological Survey.

“In case you were wondering if it was fireworks or earthquakes earlier this morning …” SCEMD said on Facebook.

While it would normally be no competition between the amount of vibrations caused by fireworks on a Fourth of July holiday weekend in South Carolina and the shaking felt from an earthquake’s tremors, the question is legitimate this year because of all the recent seismic activity.

Last Sunday, an earthquake was recorded in Elgin, according to the USGS. That led a series of earthquakes, or aftershocks, including a pair of 3.5 magnitude and 3.6 magnitude quakes on Wednesday afternoon and early evening.

Those were the two largest quakes to hit South Carolina in nearly a decade. A 4.1-magnitude quake struck McCormick County in 2014. 

Another earthquake in Georgia on June 18 reached a 3.9 magnitude and could be felt in much of South Carolina.

The recent earthquakes mean at least 50 have been detected in the Palmetto State since the start of 2022, according to South Carolina DNR. All but five of the quakes have been in the Midlands.

In all, 52 earthquakes have hit the Columbia area since a 3.3 magnitude quake was recorded on Dec. 27, 2021, according to the South Carolina Department of Natural Resources.

No major damage or injuries have been reported from any of the recent quakes.

Earthquakes that register 2.5 magnitude or less often go unnoticed and are usually only recorded by a seismograph, according to Michigan Technological University. Any quake less than 5.5 magnitude is not likely to cause significant damage, the school said.

It is typical for South Carolina to have between six and 10 earthquakes a year, the S.C. Geological Survey previously reported. There have been 77 earthquakes in South Carolina since Jan. 18, 2021, according to the S.C. Department of Natural Resources.

An explanation for the recent outburst has eluded scientists

Digging and blasting at mines, water seeping through the ground from lakes, or other changes in weight or pressure underground could all contribute to seismic activity, The State previously reported, but no one has settled on the single cause for the Midlands’ shaking. The state Department of Health and Environmental Control said last week that mining activity is not likely to be the cause of recent earthquakes, as mines in the Elgin area are shallow.

Elgin, located about 20 miles northeast of Columbia and situated on a fault line, has been experiencing an unusual earthquake “swarm” for the past several months, leaving some residents feeling uneasy. The series of quakes might be the longest period of earthquake activity in the state’s history, officials said last week. But officials have said they don’t believe the spate of minor earthquakes is an indicator that a bigger quake could be on the way.

The strongest earthquake ever recorded in South Carolina — and on the East Coast of the U.S. — was a devastating 7.3 in Charleston in 1886.

That quake killed 60 people and was felt over 2.5 million square miles, from Cuba to New York, and Bermuda to the Mississippi River, according to the Emergency Management Division.

Reported earthquakes in SC in 2021-22

Date/Location

Magnitude

Depth (km)

Jan. 18/Dalzell

2.1

6.9

Feb. 13/Summerville

2.1

5.1

May 12/Heath Springs

1.8

9.99

May 31/Summit

2.6

1.7

May 31/Summit

2.05.1

July 16/Ladson2.04.0

July 22/Ladson1.3

3.5

July 22/Ladson

1.95

3.97

Aug. 21/Centerville

1.75

1.97

Aug. 21/Centerville

1.71

3.37

Sept. 27/Summerville2.86.0

Sept. 27/Summerville

2.0

5.8

Sept. 27/Centerville

3.36.8Oct. 25/Jenkinsville2.23.8Oct. 26/Jenkinsville1.80.0Oct. 28/Jenkinsville1.81.8Oct. 28/Jenkinsville1.70.0Oct. 28/Jenkinsville2.14.2Oct. 31/Jenkinsville2.30.1Nov. 1/Jenkinsville2.05.1Nov. 9/Centerville1.53.8Nov. 16/Arial2.25.4Dec. 20/Ladson1.12.8Dec. 27/Lugoff3.33.2Dec. 27/Lugoff2.52.4Dec. 27/Elgin2.10.7Dec. 27/Lugoff1.74.9Dec. 29/Elgin2.31.6Dec. 30/Elgin2.52.5Dec. 30/Elgin2.43.8Jan. 3/Lugoff2.52.7Jan. 5/Lugoff2.60.5Jan. 5/Lugoff1.57.0Jan. 9/Ladson1.42.9Jan. 11/Elgin1.75.4Jan. 11/Lugoff2.03.2Jan. 11/Elgin1.35.0Jan. 15/Elgin1.83.5Jan. 19/Elgin1.95.0Jan. 21/Elgin1.94.8

Jan. 27/Lugoff2.11.0Feb. 2/Elgin1.53.9March 4/Elgin1.82.8March 9/Elgin2.23.6March 11/Camden2.11.2March 27/Lugoff2.11.9March 28/Centerville0.92.9April 7/Elgin2.02.9April 8/Centerville1.63.6April 22/Ladson1.13.5April 22/Taylors2.22.3May 9/Elgin3.33.1May 9/Elgin1.62.9May 9/Elgin1.784.1May 9/Elgin2.13.7May 9/Elgin2.95.6May 10/Elgin2.33.9May 10/Elgin2.86.2May 19/Elgin1.82.5May 21/Elgin1.95.6June 26/Elgin1.884.09June 29/Elgin3.52.64June 29/Elgin1.882.92June 29/Elgin3.62.95June 29/Elgin1.792.07June 29/Elgin1.513.72June 29/Elgin1.461.93June 29/Elgin2.062.22June 30/Elgin2.323.09June 30/Elgin1.442.8June 30/Elgin2.033.11June 30/Elgin2.152.56June 30/Elgin2.061.92June 30/Elgin1.492.46July 1/Elgin1.553.37July 1/Elgin2.113.83July 1/Elgin1.263.3July 1/Elgin1.684.02July 2/Elgin2.091.65July 3/Elgin1.92.1July 3/Lugoff1.63.2

‘Swarm’ of Earthquakes Hitting Before the Sixth Seal: Revelation 6

‘Swarm’ of Earthquakes Hitting South Carolina Are Getting Stronger

A so-called earthquake “swarm” that is hitting South Carolina appears to be getting stronger, researchers said this week.

Two earthquakes with a magnitude of 3.5 and 3.6, respectively, hit Wednesday close to Elgin, South Carolina, according to the U.S. Geological Survey. Days before that, a 3.4 magnitude earthquake struck in another part of the state, while a 3.9 magnitude earthquake struck near the Georgia-South Carolina state line on June 18.

Both of Wednesday’s earthquakes were the strongest to hit South Carolina since a 4.1 magnitude quake struck McCormick County in 2014.

Geologist Wendy Bohon said in a videoreleased by the state’s Emergency Management Division that they’re part of a string of about 30 quakes that have struck the state so far in 2022, which they suggested is an unusual phenomenon. She described it as an “earthquake swarm,” something common in places like Southern California.

South Carolina’s Emergency Management Division wrote on Twitter the state does in fact have several fault systems and is “one of the most seismically active states on the East Coast.”

“Swarms happen in all seismic regions and the earthquakes continue until they stop,” seismologist Lucy Jones wrote this week in reference to the quakes in South Carolina. “That may not seem helpful, but knowing this is normal can help.”

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Jones said that the swarm has been occurring for at least six months, noting seven quakes that were recorded at a magnitude of 3 or above.

But state geologists said they are not sure why the Midlands region is having so many earthquakes at the moment.

“If you can figure that out, you should go get your tux and pick up your Nobel Prize,” Thomas Pratt, regional coordinator of the Geological Survey’s earthquake hazard program, told The State newspaper. “The Eastern United States in general is not on a plate boundary, so it’s a mystery in the scientific community why in this exact location, in the middle of a plate, that something would trigger this.”

Pratt noted that swarms of quakes “can be foreshocks to a larger earthquake,” adding, “There’s no reason to think there will be, but it can’t be eliminated.”

A 7.1 magnitude earthquake was reported in Charleston in 1886, killing at least 60 people, according to historical records.

Earthquakes that are lower than 4.0 on the Richter scale generally don’t cause much damage, according to the USGS’s website.

“Most earthquakes occur where the earth’s plates come together, and they’re the result of the tension and the stress that builds up as those plates are grinding and moving, slamming into each other. That’s not happening to us here on the East Coast,” Bohon told the Weather Channel. “But there are ancient fault lines here from in the past when continents had slammed together … and they are still building up stress and strain but on a much, much slower time scale.”

USGS Evidence Shows Power of the Sixth Seal (Revelation 6:12)

New Evidence Shows Power of East Coast Earthquakes
Virginia Earthquake Triggered Landslides at Great Distances
Released: 

11/6/2012 8:30:00 AM USGS.gov

Earthquake shaking in the eastern United States can travel much farther and cause damage over larger areas than previously thought.

U.S. Geological Survey scientists found that last year’s magnitude 5.8 earthquake in Virginia triggered landslides at distances four times farther—and over an area 20 times larger—than previous research has shown.

“We used landslides as an example and direct physical evidence to see how far-reaching shaking from east coast earthquakes could be,”

said Randall Jibson, USGS scientist and lead author of this study. “Not every earthquake will trigger landslides, but we can use landslide distributions to estimate characteristics of earthquake energy and how far regional ground shaking could occur.”

“Scientists are confirming with empirical data what more than 50 million people in the eastern U.S. experienced firsthand: this was one powerful earthquake,” said USGS Director Marcia McNutt. “Calibrating the distance over which landslides occur may also help us reach back into the geologic record to look for evidence of past history of major earthquakes from the Virginia seismic zone.”

This study will help inform earthquake hazard and risk assessments as well as emergency preparedness, whether for landslides or other earthquake effects.

This study also supports existing research showing that although earthquakes  are less frequent in the East, their damaging effects can extend over a much larger area as compared to the western United States.

The research is being presented today at the Geological Society of America conference, and will be published in the December 2012 issue of the

Bulletin of the Seismological Society of America.

The USGS found that the farthest landslide from the 2011 Virginia earthquake was 245 km (150 miles) from the epicenter. This is by far the greatest landslide distance recorded from any other earthquake of similar magnitude. Previous studies of worldwide earthquakes indicated that landslides occurred no farther than 60 km (36 miles) from the epicenter of a magnitude 5.8 earthquake.

“What makes this new study so unique is that it provides direct observational evidence from the largest earthquake to occur in more than 100 years in the eastern U.S,” said Jibson. “Now that we know more about the power of East Coast earthquakes, equations that predict ground shaking might need to be revised.”

It is estimated that approximately one-third of the U.S. population could have felt last year’s earthquake in Virginia, more than any earthquake in U.S. history.

About 148,000 people reported their ground-shaking experiences caused by the earthquake on the USGS “Did You Feel It?” website. Shaking reports came from southeastern Canada to Florida and as far west as Texas.

In addition to the great landslide distances recorded, the landslides from the 2011 Virginia earthquake occurred in an area 20 times larger than expected from studies of worldwide earthquakes. Scientists plotted the landslide locations that were farthest out and then calculated the area enclosed by those landslides. The observed landslides from last year’s Virginia earthquake enclose an area of about 33,400 km2

, while previous studies indicated an expected area of about 1,500 km2

from an earthquake of similar magnitude.

“The landslide distances from last year’s Virginia earthquake are remarkable compared to historical landslides across the world and represent the largest distance limit ever recorded,” said Edwin Harp, USGS scientist and co-author of this study. “There are limitations to our research, but the bottom line is that we now have a better understanding of the power of East Coast earthquakes and potential damage scenarios.”

The difference between seismic shaking in the East versus the West is due in part to the geologic structure and rock properties that allow seismic waves to travel farther without weakening.

Learn more

about the 2011 central Virginia earthquake.

New 3.6 earthquake felt before the Sixth Seal: Revelation 6

New 3.6 earthquake felt in South Carolina, strongest one in 8 years

This was the second stronger earthquake in the central South Carolina region Wednesday.

COLUMBIA, S.C. — Another earthquake has shaken much of the Midlands, just hours after another strong tremor rattled the area.

The U.S. Geological Survey says the 3.6 magnitude quake struck at 7:03 p.m. Wednesday about 1.24 miles east of Elgin. It was at a depth of just a tenth of a mile, which is very close to the surface for an earthquake.

The USGS has confirmed two aftershocks, both at 7:22pm. One was 1.5 magnitude and the other was 1.8 magnitude. The two aftershocks happed at different times in the same minute.   

It was the seventh quake of the day. 

This week has seen 12 earthquakes. 

News19 has gotten reports of people feeling the earthquake throughout the central Midlands and up near the Charlotte area. At WLTX, we were on the air when the 3.6 quake took place and that moment was captured on-air.

Watch Below: The moment when the earthquake struck at News19 

The later tremor a bit stronger than the one that took place just hours earlier. The earlier one was a 3.5 magnitude quake that happened at 2:43 p.m. in an area 3.2 miles east of Elgin. The USGS shake map got well over 3,000 reports of people feeling it, with reports all across Richland, Kershaw, and Lexington Counties and has far north as Charlotte.  

The Kershaw County Emergency Management division says the power outages in the area were caused by the earthquake.  The earthquake triggered the switch plates which caused the power to blink off for a while. 

Three much smaller aftershocks also took place. 

Earthquakes happen throughout the state but most occur near the coast. Approximately 70 percent of earthquakes are in the coastal plain, with most happening in the Lowcountry. 

Back in 1886, Charleston was hit by a catastrophic earthquake. It had an estimated magnitude of 7.3, and was felt as far away and Cuba and New York. At least 60 people were killed, and thousands of building were damaged.

Structural damage extended hundreds of miles to cities in Alabama, Ohio, and Kentucky.

Geologists say that Charleston lies in one of the most seismically active areas in the eastern United States.

A Lack Of Vigilance Before The Sixth Seal (Revelation 6:12)

        

Faults Underlying Exercise Vigilant GuardStory by: (Author NameStaff Sgt. Raymond Drumsta – 138th Public Affairs Detachment
Dated: Thu, Nov 5, 2009
This map illustrates the earthquake fault lines in Western New York. An earthquake in the region is a likely event, says University of Buffalo Professor Dr. Robert Jacobi.
TONAWANDA, NY — An earthquake in western New York, the scenario that Exercise Vigilant Guard is built around, is not that far-fetched, according to University of Buffalo geology professor Dr. Robert Jacobi.
When asked about earthquakes in the area, Jacobi pulls out a computer-generated state map, cross-hatched with diagonal lines representing geological faults.
The faults show that past earthquakes in the state were not random, and could occur again on the same fault systems, he said.
“In western New York, 6.5 magnitude earthquakes are possible,” he said.
This possibility underlies Exercise Vigilant Guard, a joint training opportunity for National Guard and emergency response organizations to build relationships with local, state, regional and federal partners against a variety of different homeland security threats including natural disasters and potential terrorist attacks.
The exercise was based on an earthquake scenario, and a rubble pile at the Spaulding Fibre site here was used to simulate a collapsed building. The scenario was chosen as a result of extensive consultations with the earthquake experts at the University of Buffalo’s Multidisciplinary Center for Earthquake Engineering Research (MCEER), said Brig. Gen. Mike Swezey, commander of 53rd Troop Command, who visited the site on Monday.
Earthquakes of up to 7 magnitude have occurred in the Northeastern part of the continent, and this scenario was calibrated on the magnitude 5.9 earthquake which occurred in Saguenay, Quebec in 1988, said Jacobi and Professor Andre Filiatrault, MCEER director.
“A 5.9 magnitude earthquake in this area is not an unrealistic scenario,” said Filiatrault.
Closer to home, a 1.9 magnitude earthquake occurred about 2.5 miles from the Spaulding Fibre site within the last decade, Jacobi said. He and other earthquake experts impaneled by the Atomic Energy Control Board of Canada in 1997 found that there’s a 40 percent chance of 6.5 magnitude earthquake occurring along the Clareden-Linden fault system, which lies about halfway between Buffalo and Rochester, Jacobi added.
Jacobi and Filiatrault said the soft soil of western New York, especially in part of downtown Buffalo, would amplify tremors, causing more damage.
“It’s like jello in a bowl,” said Jacobi.
The area’s old infrastructure is vulnerable because it was built without reinforcing steel, said Filiatrault. Damage to industrial areas could release hazardous materials, he added.
“You’ll have significant damage,” Filiatrault said.
Exercise Vigilant Guard involved an earthquake’s aftermath, including infrastructure damage, injuries, deaths, displaced citizens and hazardous material incidents. All this week, more than 1,300 National Guard troops and hundreds of local and regional emergency response professionals have been training at several sites in western New York to respond these types of incidents.
Jacobi called Exercise Vigilant Guard “important and illuminating.”
“I’m proud of the National Guard for organizing and carrying out such an excellent exercise,” he said.
Training concluded Thursday.

New York Earthquake: City of the Sixth Seal (Revelation 6:12)

New York earthquake: City at risk of ‚dangerous shaking from far away‘
Joshua Nevett
Published 30th April 2018
SOME of New York City’s tallest skyscrapers are at risk of being shaken by seismic waves triggered by powerful earthquakes from miles outside the city, a natural disaster expert has warned.
Researchers believe that a powerful earthquake, magnitude 5 or greater, could cause significant damage to large swathes of NYC, a densely populated area dominated by tall buildings.
A series of large fault lines that run underneath NYC’s five boroughs, Manhattan, Brooklyn, Queens, The Bronx and Staten Island, are capable of triggering large earthquakes.
Some experts have suggested that NYC is susceptible to at least a magnitude 5 earthquake once every 100 years.
The last major earthquake measuring over magnitude 5.0 struck NYC in 1884 – meaning another one of equal size is “overdue” by 34 years, according their prediction model.
Natural disaster researcher Simon Day, of University College London, agrees with the conclusion that NYC may be more at risk from earthquakes than is usually thought.
EARTHQUAKE RISK: New York is susceptible to seismic shaking from far-away tremors
But the idea of NYC being “overdue” for an earthquake is “invalid”, not least because the “very large number of faults” in the city have individually low rates of activity, he said.
The model that predicts strong earthquakes based on timescale and stress build-up on a given fault has been “discredited”, he said.
What scientists should be focusing on, he said, is the threat of large and potentially destructive earthquakes from “much greater distances”.
The dangerous effects of powerful earthquakes from further away should be an “important feature” of any seismic risk assessment of NYC, Dr Day said.

GETTY
THE BIG APPLE: An aerial view of Lower Manhattan at dusk in New York City

USGS
RISK: A seismic hazard map of New York produced by USGS
“New York is susceptible to seismic shaking from earthquakes at much greater distances” Dr Simon Day, natural disaster researcher
This is because the bedrock underneath parts of NYC, including Long Island and Staten Island, cannot effectively absorb the seismic waves produced by earthquakes.
“An important feature of the central and eastern United States is, because the crust there is old and cold, and contains few recent fractures that can absorb seismic waves, the rate of seismic reduction is low.
Central regions of NYC, including Manhattan, are built upon solid granite bedrock; therefore the amplification of seismic waves that can shake buildings is low.
But more peripheral areas, such as Staten Island and Long Island, are formed by weak sediments, meaning seismic hazard in these areas is “very likely to be higher”, Dr Day said.
“Thus, like other cities in the eastern US, New York is susceptible to seismic shaking from earthquakes at much greater distances than is the case for cities on plate boundaries such as Tokyo or San Francisco, where the crustal rocks are more fractured and absorb seismic waves more efficiently over long distances,” Dr Day said.
In the event of a large earthquake, dozens of skyscrapers, including Chrysler Building, the Woolworth Building and 40 Wall Street, could be at risk of shaking.
“The felt shaking in New York from the Virginia earthquake in 2011 is one example,” Dr Day said.
On that occasion, a magnitude 5.8 earthquake centered 340 miles south of New York sent thousands of people running out of swaying office buildings.

USGS
FISSURES: Fault lines in New York City have low rates of activity, Dr Day said
NYC Mayor Michael Bloomberg said the city was “lucky to avoid any major harm” as a result of the quake, whose epicenter was near Louisa, Virginia, about 40 miles from Richmond.
“But an even more impressive one is the felt shaking from the 1811-1812 New Madrid earthquakes in the central Mississippi valley, which was felt in many places across a region, including cities as far apart as Detroit, Washington DC and New Orleans, and in a few places even further afield including,” Dr Day added.
“So, if one was to attempt to do a proper seismic hazard assessment for NYC, one would have to include potential earthquake sources over a wide region, including at least the Appalachian mountains to the southwest and the St Lawrence valley to the north and east.”

New York Subways at the Sixth Seal (Revelation 6)

          

How vulnerable are NYC’s underwater subway tunnels to flooding?Ashley Fetters
New York City is full of peculiar phenomena—rickety fire escapes; 100-year-old subway tunnelsair conditioners propped perilously into window frames—that can strike fear into the heart of even the toughest city denizen. But should they? Every month, writer Ashley Fetters will be exploring—and debunking—these New York-specific fears, letting you know what you should actually worry about, and what anxieties you can simply let slip away.
The 25-minute subway commute from Crown Heights to the Financial District on the 2/3 line is, in my experience, a surprisingly peaceful start to the workday—save for one 3,100-foot stretch between the Clark Street and Wall Street stations, where for three minutes I sit wondering what the probability is that I will soon die a torturous, claustrophobic drowning death right here in this subway car.
The Clark Street Tunnel, opened in 1916, is one of approximately a dozen tunnels that escort MTA passengers from one borough to the next underwater—and just about all of them, with the exception of the 1989 addition of the 63rd Street F train tunnel, were constructed between 1900 and 1936.
Each day, thousands of New Yorkers venture across the East River and back again through these tubes buried deep in the riverbed, some of which are nearing or even past their 100th birthdays. Are they wrong to ponder their own mortality while picturing one of these watery catacombs suddenly springing a leak?
Mostly yes, they are, says Michael Horodniceanu, the former president of MTA Capital Construction and current principal of Urban Advisory Group. First, it’s important to remember that the subway tunnel is built under the riverbed, not just in the river—so what immediately surrounds the tunnel isn’t water but some 25 feet of soil. “There’s a lot of dirt on top of it,” Horodniceanu says. “It’s well into the bed of the bottom of the channel.”
And second, as Angus Kress Gillespie, author of Crossing Under the Hudson: The Story of the Holland and Lincoln Tunnels, points out, New York’s underwater subway tunnels are designed to withstand some leaking. And withstand it they do: Pumps placed below the floor of the tunnel, he says, are always running, always diverting water seepage into the sewers. (Horodniceanu says the amount of water these pumps divert into the sewer system each day numbers in the thousands of gallons.)
Additionally, MTA crews routinely repair the grouting and caulking, and often inject a substance into the walls that creates a waterproof membrane outside the tunnel—which keeps water out of the tunnel and relieves any water pressure acting on its walls. New tunnels, Horodniceanu points out, are even built with an outside waterproofing membrane that works like an umbrella: Water goes around it, it falls to the sides, and then it gets channeled into a pumping station and pumped out.
Of course, the classic New York nightmare scenario isn’t just a cute little trickle finding its way in. The anxiety daydream usually involves something sinister, or seismic. The good news, however, is that while an earthquake or explosion would indeed be bad for many reasons, it likely wouldn’t result in the frantic flooding horror scene that plays out in some commuters’ imaginations.
The Montague Tube, which sustained severe damage during Hurricane Sandy.
MTA New York City Transit / Marc A. Hermann
Horodniceanu assures me that tunnels built more recently are “built to withstand a seismic event.” The older tunnels, however—like, um, the Clark Street Tunnel—“were not seismically retrofitted, let me put it that way,” Horodniceanu says. “But the way they were built is in such a way that I do not believe an earthquake would affect them.” They aren’t deep enough in the ground, anyway, he says, to be too intensely affected by a seismic event. (The MTA did not respond to a request for comment.)
One of the only real threats to tunnel infrastructure, Horodniceanu adds, is extreme weather. Hurricane Sandy, for example, caused flooding in the tunnels, which “created problems with the infrastructure.” He continues, “The tunnels have to be rebuilt as a result of saltwater corroding the infrastructure.”
Still, he points out, hurricanes don’t exactly happen with no warning. So while Hurricane Sandy did cause major trauma to the tunnels, train traffic could be stopped with ample time to keep passengers out of harm’s way. In 2012, Governor Andrew Cuomo directed all the MTA’s mass transit services to shut down at 7 p.m. the night before Hurricane Sandy was expected to hit New York City.
And Gillespie, for his part, doubts even an explosion would result in sudden, dangerous flooding. A subway tunnel is not a closed system, he points out; it’s like a pipe that’s open at both ends. “The force of a blast would go forwards and backwards out the exit,” he says.
So the subway-train version of that terrifying Holland Tunnel flood scene in Sylvester Stallone’s Daylight is … unrealistic, right?
“Yeah,” Gillespie laughs. “Yeah. It is.”
Got a weird New York anxiety that you want explored? E-mail tips@curbed.com, and we may include it in a future column.

The sixth shake before the sixth seal: Revelation 6

The sixth earthquake in four days rocks the SC Midlands. What to know

COLUMBIA, S.C. — Another earthquake shook up the South Carolina Midlands Thursday morning.

The earthquake hit at around 7 a.m. about 20 miles outside of Columbia, according to the United States Geological Survey. The 2.5 magnitude had it’s epicenters near Elgin.

This is the sixth earthquake since Dec. 27 when a 3.3 magnitude quake was reported. People reported feeling shaking and hearing a loud boom during some of the other quakes. All the seismic activity has been centered near Elgin or neighboring Lugoff. The other four earthquakes have been 2.5 magnitude or lower.

An earthquake of 2.5 magnitude is considered minor, according to seismologists. For the most part quakes that register 2.5 magnitude or less go unnoticed and are only recorded by a seismograph. Any quake less than 5.5 magnitude is not likely to cause significant damage.

Earthquakes can happen in clusters, seismologist say.


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