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

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

Monday, March 14, 2011

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.

“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.

“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.

THE SIXTH SEAL: NEW YORK CITY (REV 6:12)

Earthquake activity in the New York City area

Wikipedia

Although the eastern United States is not as seismically active as regions near plate boundaries, large and damaging earthquakes do occur there. Furthermore, when these rare eastern U.S. earthquakes occur, the areas affected by them are much larger than for western U.S. earthquakes of the same magnitude. Thus, earthquakes represent at least a moderate hazard to East Coast cities, including New York City and adjacent areas of very high population density.

Seismicity in the vicinity of New York City. Data are from the U.S. Geological Survey (Top, USGS) and the National Earthquake Information Center (Bottom, NEIC). In the top figure, closed red circles indicate 1924-2006 epicenters and open black circles indicate locations of the larger earthquakes that occurred in 1737, 1783 and 1884. Green lines indicate the trace of the Ramapo fault.

As can be seen in the maps of earthquake activity in this region(shown in the figure), seismicity is scattered throughout most of the New York City area, with some hint of a concentration of earthquakes in the area surrounding Manhattan Island. The largest known earthquake in this region occurred in 1884 and had a magnitude of approximately 5.For this earthquake, observations of fallen bricks and cracked plaster were reported from eastern Pennsylvania to central Connecticut, and the maximum intensity reported was at two sites in western Long Island (Jamaica, New York and Amityville, New York). Two other earthquakes of approximately magnitude 5 occurred in this region in 1737 and 1783. The figure on the right shows maps of the distribution of earthquakes of magnitude 3 and greater that occurred in this region from 1924 to 2010, along with locations of the larger earthquakes that occurred in 1737, 1783 and 1884.

Background

The NYC area is part of the geologically complex structure of the Northern Appalachian Mountains. This complex structure was formed during the past half billion years when the Earth’s crust underlying the Northern Appalachians was the site of two major geological episodes, each of which has left its imprint on the NYC area bedrock. Between about 450 million years ago and about 250 million years ago, the Northern Appalachian region was affected by a continental collision, in which the ancient African continent collided with the ancient North American continent to form the supercontinent Pangaea. Beginning about 200 million years ago, the present-day Atlantic ocean began to form as plate tectonic forces began to rift apart the continent of Pangaea. The last major episode of geological activity to affect the bedrock in the New York area occurred about 100 million years ago, during the Mesozoic era, when continental rifting that led to the opening of the present-day Atlantic ocean formed the Hartford and Newark Mesozoic rift basins.

Earthquake rates in the northeastern United States are about 50 to 200 times lower than in California, but the earthquakes that do occur in the northeastern U.S. are typically felt over a much broader region than earthquakes of the same magnitude in the western U.S.This means the area of damage from an earthquake in the northeastern U.S. could be larger than the area of damage caused by an earthquake of the same magnitude in the western U.S. The cooler rocks in the northeastern U.S. contribute to the seismic energy propagating as much as ten times further than in the warmer rocks of California. A magnitude 4.0 eastern U.S. earthquake typically can be felt as far as 100 km (60 mi) from its epicenter, but it infrequently causes damage near its source. A magnitude 5.5 eastern U.S. earthquake, although uncommon, can be felt as far as 500 km (300 mi) from its epicenter, and can cause damage as far away as 40 km (25 mi) from its epicenter. Earthquakes stronger than about magnitude 5.0 generate ground motions that are strong enough to be damaging in the epicentral area.

At well-studied plate boundaries like the San Andreas fault system in California, scientists can often make observations that allow them to identify the specific fault on which an earthquake took place. In contrast, east of the Rocky Mountains this is rarely the case.  The NYC area is far from the boundaries of the North American plate, which are in the center of the Atlantic Ocean, in the Caribbean Sea, and along the west coast of North America. The seismicity of the northeastern U.S. is generally considered to be due to ancient zones of weakness that are being reactivated in the present-day stress field. In this model, pre-existing faults that were formed during ancient geological episodes persist in the intraplate crust, and the earthquakes occur when the present-day stress is released along these zones of weakness. The stress that causes the earthquakes is generally considered to be derived from present-day rifting at the Mid-Atlantic ridge.

Earthquakes and geologically mapped faults in the Northeastern U.S.

The northeastern U.S. has many known faults, but virtually all of the known faults have not been active for perhaps 90 million years or more. Also, the locations of the known faults are not well determined at earthquake depths. Accordingly, few (if any) earthquakes in the region can be unambiguously linked to known faults. Given the current geological and seismological data, it is difficult to determine if a known fault in this region is still active today and could produce a modern earthquake. As in most other areas east of the Rocky Mountains, the best guide to earthquake hazard in the northeastern U.S. is probably the locations of the past earthquakes themselves.

The Ramapo fault and other New York City area faults

The Ramapo Fault, which marks the western boundary of the Newark rift basin, has been argued to be a major seismically active feature of this region,but it is difficult to discern the extent to which the Ramapo fault (or any other specific mapped fault in the area) might be any more of a source of future earthquakes than any other parts of the region. The Ramapo Fault zone spans more than 185 miles (300 kilometers) in New York, New Jersey, and Pennsylvania. It is a system of faults between the northern Appalachian Mountains and Piedmont areas to the east. This fault is perhaps the best known fault zone in the Mid-Atlantic region, and some small earthquakes have been known to occur in its vicinity. Recently, public knowledge about the fault has increased – especially after the 1970s, when the fault’s proximity to the Indian Point nuclear plant in New York was noticed.

There is insufficient evidence to unequivocally demonstrate any strong correlation of earthquakes in the New York City area with specific faults or other geologic structures in this region. The damaging earthquake affecting New York City in 1884 was probably not associated with the Ramapo fault because the strongest shaking from that earthquake occurred on Long Island (quite far from the trace of the Ramapo fault). The relationship between faults and earthquakes in the New York City area is currently understood to be more complex than any simple association of a specific earthquake with a specific mapped fault.

A 2008 study argued that a magnitude 6 or 7 earthquake might originate from the Ramapo fault zone, which would almost definitely spawn hundreds or even thousands of fatalities and billions of dollars in damage. Studying around 400 earthquakes over the past 300 years, the study also argued that there was an additional fault zone extending from the Ramapo Fault zone into southwestern Connecticut. As can be seen in the above figure of seismicity, earthquakes are scattered throughout this region, with no particular concentration of activity along the Ramapo fault, or along the hypothesized fault zone extending into southwestern Connecticut.

Just off the northern terminus of the Ramapo fault is the Indian Point Nuclear Power Plant, built between 1956 and 1960 by Consolidated Edison Company. The plant began operating in 1963, and it has been the subject of a controversy over concerns that an earthquake from the Ramapo fault will affect the power plant. Whether or not the Ramapo fault actually does pose a threat to this nuclear power plant remains an open question.

New York Quake Overdue (The Sixth Seal) (Rev 6:12)

New York City Is Overdue For Large Earthquake: Seismologist

http://www.gothamgazette.com/graphics/2008/09/skyesfig3_cropped.gif

Won-Young Kim, who runs the seismographic network for the Northeast at Columbia University’s Lamont-Doherty Earth Observatory, said the city is well overdue for a big earthquake.

The last big quake to hit New York City was a 5.3-magnitude tremor in 1884 that happened at sea in between Brooklyn and Sandy Hook. While no one was killed, buildings were damaged.

Kim said the city is likely to experience a big earthquake every 100 years or so.

“It can happen anytime soon,” Kim said. “We can expect it any minute, we just don’t know when and where.”

New York has never experienced a magnitude 6 or 7 earthquake, which are the most dangerous. But magnitude 5 quakes could topple brick buildings and chimneys.

Seismologist John Armbruster said a magnitude 5 quake that happened now would be more devastating than the one that happened in 1884.

Authorities Expecting The Sixth Seal? (Revelation 6:12)

New York Times

By SAM ROBERTS

JULY 17, 2014

Here is another reason to buy a mega-million-dollar apartment in a Manhattan high-rise: Earthquake forecast maps for New York City that a federal agency issued on Thursday indicate “a slightly lower hazard for tall buildings than previously thought.”

The agency, the United States Geodetic Survey, tempered its latest quake prediction with a big caveat.

Federal seismologists based their projections of a lower hazard for tall buildings — “but still a hazard nonetheless,” they cautioned — on a lower likelihood of slow shaking from an earthquake occurring near the city, the type of shaking that typically causes more damage to taller structures.

“The tall buildings in Manhattan are not where you should be focusing,” said John Armbruster, a seismologist with the Lamont-Doherty Earth Observatory of Columbia University. “They resonate with long period waves. They are designed and engineered to ride out an earthquake. Where you should really be worried in New York City is the common brownstone and apartment building and buildings that are poorly maintained.”

Mr. Armbruster was not involved in the federal forecast, but was an author of an earlier study that suggested that “a pattern of subtle but active faults makes the risk of earthquakes to the New York City area substantially greater than formerly believed.”

He noted that barely a day goes by without a New York City building’s being declared unsafe, without an earthquake. “If you had 30, 40, 50 at one time, responders would be overloaded,” he said.

The city does have an earthquake building code that went into effect in 1996, and that applies primarily to new construction.

A well-maintained building would probably survive a magnitude 5 earthquake fairly well, he said. The last magnitude 5 earthquake in the city struck in 1884. Another is not necessarily inevitable; faults are more random and move more slowly than they do in, say, California. But he said the latest federal estimate was probably raised because of the magnitude of the Virginia quake.

Mr. Armbruster said the Geodetic Survey forecast would not affect his daily lifestyle. “I live in a wood-frame building with a brick chimney and I’m not alarmed sitting up at night worried about it,” he said. “But society’s leaders need to take some responsibility.”

PG&E Prepare for the Third Woe

PG&E Conducts Earthquake Exercise at New Emergency Operations Facility

Pacific Gas and Electric Co. (PG&E) conducted a large-scale earthquake exercise on Jan. 23, at its new emergency operations center in Vacaville.

Hundreds of PG&E employees at that location, and elsewhere across the service area, took part in the emergency exercise that simulated a magnitude 7.0 earthquake with the epicenter near Oakland and subsequent aftershocks in the East Bay Area.

The company was joined by representatives of several agencies, as either observers or participants, including the Edison Electric Institute (EEI), the California Office of Emergency Services, the Federal Emergency Management Agency (FEMA), Bay Area Rapid Transit (BART), the California Public Utilities Commission (CPUC), the California Independent System Operator (CAISO) and the Department of Energy (DOE).

The simulated quake caused massive damage throughout the nine-county Bay Area — about 1.5 million PG&E electric customers and about 200,000 gas customers lost service. Assessments began shortly after the quake but the company told customers that full restoration could take weeks, even with a large influx of mutual-aid and contract crews.

Under the direction of the emergency operations center commander, PG&E employees from nearly every organization, from gas and electric operations to corporate security and customer care, took part in the exercise.

“We live in an earthquake country and seismologists say that the Big One is not a matter of if, but when. The PG&E has a plan and we practiced executing that plan in a real-world scenario. It’s vitally important that our customers are prepared too — by having individual and family emergency plans and go bags — and making sure the PG&E has your updated contact information,” said Mark Quinlan, senior director of emergency preparedness and response for the PG&E.

The 30,000-sq ft PG&E Vacaville Emergency Response Center opened in 2019. A purpose-built critical facility, it has redundant utility power, backup generator power, and backup and telecom infrastructure. To improve earthquake structural resilience, the facility was constructed to a 1.5 importance factor, which is 50% above the California commercial building standard. It contains emergency operations for electric, gas, and energy procurement.

History Expects the Sixth Seal in NYC (Revelation 6:12)

According to the New York Daily News, Lynn Skyes, lead author of a recent study by seismologists at the Lamont-Doherty Earth Observatory adds that a magnitude-6 quake hits the area about every 670 years, and magnitude-7 every 3,400 years.

A 5.2-magnitude quake shook New York City in 1737 and another of the same severity hit in 1884.

Tremors were felt from Maine to Virginia.

There are several fault lines in the metro area, including one along Manhattan’s 125th St. – which may have generated two small tremors in 1981 and may have been the source of the major 1737 earthquake, says Armbruster.

“The problem here comes from many subtle faults,” explained Skyes after the study was published.

He adds: “We now see there is earthquake activity on them. Each one is small, but when you add them up, they are probably more dangerous than we thought.”

Armbruster says a 5.0-magnitude earthquake today likely would result in casualties and hundreds of millions of dollars in damage.

“I would expect some people to be killed,” he notes.

The scope and scale of damage would multiply exponentially with each additional tick on the Richter scale. (ANI)

Quakeland: New York and the Sixth Seal

Quakeland: On the Road to America’s Next Devastating Earthquake

Roger Bilham

Given recent seismic activity — political as well as geological — it’s perhaps unsurprising that two books on earthquakes have arrived this season. One is as elegant as the score of a Beethoven symphony; the other resembles a diary of conversations overheard during a rock concert. Both are interesting, and both relate recent history to a shaky future.

Journalist Kathryn Miles’s Quakeland is a litany of bad things that happen when you provoke Earth to release its invisible but ubiquitous store of seismic-strain energy, either by removing fluids (oil, water, gas) or by adding them in copious quantities (when extracting shale gas in hydraulic fracturing, also known as fracking, or when injecting contaminated water or building reservoirs). To complete the picture, she describes at length the bad things that happen during unprovoked natural earthquakes. As its subtitle hints, the book takes the form of a road trip to visit seismic disasters both past and potential, and seismologists and earthquake engineers who have first-hand knowledge of them. Their colourful personalities, opinions and prejudices tell a story of scientific discovery and engineering remedy.

Miles poses some important societal questions. Aside from human intervention potentially triggering a really damaging earthquake, what is it actually like to live in neighbourhoods jolted daily by magnitude 1–3 earthquakes, or the occasional magnitude 5? Are these bumps in the night acceptable? And how can industries that perturb the highly stressed rocks beneath our feet deny obvious cause and effect? In 2015, the Oklahoma Geological Survey conceded that a quadrupling of the rate of magnitude-3 or more earthquakes in recent years, coinciding with a rise in fracking, was unlikely to represent a natural process. Miles does not take sides, but it’s difficult for the reader not to.

She visits New York City, marvelling at subway tunnels and unreinforced masonry almost certainly scheduled for destruction by the next moderate earthquake in the vicinity. She considers the perils of nuclear-waste storage in Nevada and Texas, and ponders the risks to Idaho miners of rock bursts — spontaneous fracture of the working face when the restraints of many million years of confinement are mined away. She contemplates the ups and downs of the Yellowstone Caldera — North America’s very own mid-continent supervolcano — and its magnificently uncertain future. Miles also touches on geothermal power plants in southern California’s Salton Sea and elsewhere; the vast US network of crumbling bridges, dams and oil-storage farms; and the magnitude 7–9 earthquakes that could hit California and the Cascadia coastline of Oregon and Washington state this century. Amid all this doom, a new elementary school on the coast near Westport, Washington, vulnerable to inbound tsunamis, is offered as a note of optimism. With foresight and much persuasion from its head teacher, it was engineered to become an elevated safe haven.

Miles briefly discusses earthquake prediction and the perils of getting it wrong (embarrassment in New Madrid, Missouri, where a quake was predicted but never materialized; prison in L’Aquila, Italy, where scientists failed to foresee a devastating seismic event) and the successes of early-warning systems, with which electronic alerts can be issued ahead of damaging seismic waves. Yes, it’s a lot to digest, but most of the book obeys the laws of physics, and it is a engaging read. One just can’t help wishing that Miles’s road trips had taken her somewhere that wasn’t a disaster waiting to happen.

Catastrophic damage in Anchorage, Alaska, in 1964, caused by the second-largest earthquake in the global instrumental record.

In The Great Quake, journalist Henry Fountain provides us with a forthright and timely reminder of the startling historical consequences of North America’s largest known earthquake, which more than half a century ago devastated southern Alaska. With its epicentre in Prince William Sound, the 1964 quake reached magnitude 9.2, the second largest in the global instrumental record. It released more energy than either the 2004 Sumatra–Andaman earthquake or the 2011 Tohoku earthquake off Japan; and it generated almost as many pages of scientific commentary and description as aftershocks. Yet it has been forgotten by many.

The quake was scientifically important because it occurred at a time when plate tectonics was in transition from hypothesis to theory. Fountain expertly traces the theory’s historical development, and how the Alaska earthquake was pivotal in nailing down one of the most important predictions. The earthquake caused a fjordland region larger than England to subside, and a similarly huge region of islands offshore to rise by many metres; but its scientific implications were not obvious at the time. Eminent seismologists thought that a vertical fault had slipped, drowning forests and coastlines to its north and raising beaches and islands to its south. But this kind of fault should have reached the surface, and extended deep into Earth’s mantle. There was no geological evidence of a monster surface fault separating these two regions, nor any evidence for excessively deep aftershocks. The landslides and liquefied soils that collapsed houses, and the tsunami that severely damaged ports and infrastructure, offered no clues to the cause.

“Previous earthquakes provide clear guidance about present-day vulnerability.” The hero of The Great Quake is the geologist George Plafker, who painstakingly mapped the height reached by barnacles lifted out of the intertidal zone along shorelines raised by the earthquake, and documented the depths of drowned forests. He deduced that the region of subsidence was the surface manifestation of previously compressed rocks springing apart, driving parts of Alaska up and southwards over the Pacific Plate. His finding confirmed a prediction of plate tectonics, that the leading edge of the Pacific Plate plunged beneath the southern edge of Alaska along a gently dipping thrust fault. That observation, once fully appreciated, was applauded by the geophysics community.

Fountain tells this story through the testimony of survivors, engineers and scientists, interweaving it with the fascinating history of Alaska, from early discovery by Europeans to purchase from Russia by the United States in 1867, and its recent development. Were the quake to occur now, it is not difficult to envisage that with increased infrastructure and larger populations, the death toll and price tag would be two orders of magnitude larger than the 139 fatalities and US$300-million economic cost recorded in 1964.

What is clear from these two books is that seismicity on the North American continent is guaranteed to deliver surprises, along with unprecedented economic and human losses. Previous earthquakes provide clear guidance about the present-day vulnerability of US infrastructure and populations. Engineers and seismologists know how to mitigate the effects of future earthquakes (and, in mid-continent, would advise against the reckless injection of waste fluids known to trigger earthquakes). It is merely a matter of persuading city planners and politicians that if they are tempted to ignore the certainty of the continent’s seismic past, they should err on the side of caution when considering its seismic future.

East Coast Still Unprepared For The Sixth Seal (Rev 6:12)

East Coast Earthquake Preparedness

By By BEN NUCKOLS

Posted: 08/25/2011 8:43 am EDT

WASHINGTON — There were cracks in the Washington Monument and broken capstones at the National Cathedral. In the District of Columbia suburbs, some people stayed in shelters because of structural concerns at their apartment buildings.

A day after the East Coast’s strongest earthquake in 67 years, inspectors assessed the damage and found that most problems were minor. But the shaking raised questions about whether this part of the country, with its older architecture and inexperience with seismic activity, is prepared for a truly powerful quake.

The 5.8 magnitude quake felt from Georgia north to Canada prompted swift inspections of many structures Wednesday, including bridges and nuclear plants. An accurate damage estimate could take weeks, if not longer. And many people will not be covered by insurance.

In a small Virginia city near the epicenter, the entire downtown business district was closed. School was canceled for two weeks to give engineers time to check out cracks in several buildings.

At the 555-foot Washington Monument, inspectors found several cracks in the pyramidion – the section at the top of the obelisk where it begins narrowing to a point.

A 4-foot crack was discovered Tuesday during a visual inspection by helicopter. It cannot be seen from the ground. Late Wednesday, the National Park Service announced that structural engineers had found several additional cracks inside the top of the monument.

Carol Johnson, a park service spokeswoman, could not say how many cracks were found but said three or four of them were “significant.” Two structural engineering firms that specialize in assessing earthquake damage were being brought in to conduct a more thorough inspection on Thursday.

The monument, by far the tallest structure in the nation’s capital, was to remain closed indefinitely, and Johnson said the additional cracks mean repairs are likely to take longer. It has never been damaged by a natural disaster, including earthquakes in Virginia in 1897 and New York in 1944.

Tourists arrived at the monument Wednesday morning only to find out they couldn’t get near it. A temporary fence was erected in a wide circle about 120 feet from the flags that surround its base. Walkways were blocked by metal barriers manned by security guards.

“Is it really closed?” a man asked the clerk at the site’s bookstore.

“It’s really closed,” said the clerk, Erin Nolan. Advance tickets were available for purchase, but she cautioned against buying them because it’s not clear when the monument will open.

“This is pretty much all I’m going to be doing today,” Nolan said.

Tuesday’s quake was centered about 40 miles northwest of Richmond, 90 miles south of Washington and 3.7 miles underground. In the nearby town of Mineral, Va., Michael Leman knew his Main Street Plumbing & Electrical Supply business would need – at best – serious and expensive repairs.

At worst, it could be condemned. The facade had become detached from the rest of the building, and daylight was visible through a 4- to 6-inch gap that opened between the front wall and ceiling.

“We’re definitely going to open back up,” Leman said. “I’ve got people’s jobs to look out for.”

Leman said he is insured, but some property owners might not be so lucky.

The Insurance Information Institute said earthquakes are not covered under standard U.S. homeowners or business insurance policies, although supplemental coverage is usually available.

The institute says coverage for other damage that may result from earthquakes, such as fire and water damage from burst gas or water pipes, is provided by standard homeowners and business insurance policies in most states. Cars and other vehicles with comprehensive insurance would also be protected.

The U.S. Geological Survey classified the quake as Alert Level Orange, the second-most serious category on its four-level scale. Earthquakes in that range lead to estimated losses between $100 million and $1 billion.

In Culpeper, Va., about 35 miles from the epicenter, walls had buckled at the old sanctuary at St. Stephen’s Episcopal Church, which was constructed in 1821 and drew worshippers including Confederate Gens. Robert E. Lee and J.E.B. Stuart. Heavy stone ornaments atop a pillar at the gate were shaken to the ground. A chimney from the old Culpeper Baptist Church built in 1894 also tumbled down.

At the Washington National Cathedral, spokesman Richard Weinberg said the building’s overall structure remains sound and damage was limited to “decorative elements.”

Massive stones atop three of the four spires on the building’s central tower broke off, crashing onto the roof. At least one of the spires is teetering badly, and cracks have appeared in some flying buttresses.

Repairs were expected to cost millions of dollars – an expense not covered by insurance.

“Every single portion of the exterior is carved by hand, so everything broken off is a piece of art,” Weinberg said. “It’s not just the labor, but the artistry of replicating what was once there.”

The building will remain closed as a precaution. Services to dedicate the memorial honoring Rev. Martin Luther King Jr. were moved.

Other major cities along the East Coast that felt the shaking tried to gauge the risk from another quake.

A few hours after briefly evacuating New York City Hall, Mayor Michael Bloomberg said the city’s newer buildings could withstand a more serious earthquake. But, he added, questions remain about the older buildings that are common in a metropolis founded hundreds of years ago.

“We think that the design standards of today are sufficient against any eventuality,” he said. But “there are questions always about some very old buildings. … Fortunately those tend to be low buildings, so there’s not great danger.”

An earthquake similar to the one in Virginia could do billions of dollars of damage if it were centered in New York, said Barbara Nadel, an architect who specializes in securing buildings against natural disasters and terrorism.

The city’s 49-page seismic code requires builders to prepare for significant shifting of the earth. High-rises must be built with certain kinds of bracing, and they must be able to safely sway at least somewhat to accommodate for wind and even shaking from the ground, Nadel said.

Buildings constructed in Boston in recent decades had to follow stringent codes comparable to anything in California, said Vernon Woodworth, an architect and faculty member at the Boston Architectural College. New construction on older structures also must meet tough standards to withstand severe tremors, he said.

It’s a different story with the city’s older buildings. The 18th- and 19th-century structures in Boston’s Back Bay, for instance, were often built on fill, which can liquefy in a strong quake, Woodworth said. Still, there just aren’t many strong quakes in New England.

The last time the Boston area saw a quake as powerful as the one that hit Virginia on Tuesday was in 1755, off Cape Ann, to the north. A repeat of that quake would likely cause deaths, Woodworth said. Still, the quakes are so infrequent that it’s difficult to weigh the risks versus the costs of enacting tougher building standards regionally, he said.

People in several of the affected states won’t have much time to reflect before confronting another potential emergency. Hurricane Irene is approaching the East Coast and could skirt the Mid-Atlantic region by the weekend and make landfall in New England after that.

In North Carolina, officials were inspecting an aging bridge that is a vital evacuation route for people escaping the coastal barrier islands as the storm approaches.

Speaking at an earthquake briefing Wednesday, Washington Mayor Vincent Gray inadvertently mixed up his disasters.

“Everyone knows, obviously, that we had a hurricane,” he said before realizing his mistake.

“Hurricane,” he repeated sheepishly as reporters and staffers burst into laughter. “I’m getting ahead of myself!”

___

Associated Press writers Sam Hananel in Washington; Alex Dominguez in Baltimore; Bob Lewis in Mineral, Va.; Samantha Gross in New York City; and Jay Lindsay in Boston contributed to this report.

The Ramapo Fault and the Sixth Seal (Revelation 6:12)

https://upload.wikimedia.org/wikipedia/commons/f/f9/RamapoFaultSystem.png 

Living on the Fault Line

Posted June 15, 2010 by Wayne J. Guglielmo

The couple checked with Burns’s parents, who live in nearby Basking Ridge, and they, too, had heard and felt something, which they thought might have been an earthquake. A call by Burns some 20 minutes later to the Bernardsville Police Department—one of many curious and occasionally panicky inquiries that Sunday morning, according to the officer in charge, Sergeant John Remian—confirmed their suspicion: A magnitude 2.6 earthquake, its epicenter in Peapack/Gladstone, about seven miles from Bernardsville, had hit the area. A smaller aftershock followed about two and a half hours later.

After this year’s epic earthquakes in Haiti, Chile, Mexico, Indonesia, and China, the 2.6 quake and aftershock that shook parts of New Jersey in February may seem minor league, even to the Somerset County residents who experienced them. On the exponential Richter Scale, a magnitude 7.0 quake like the one that hit Haiti in January is almost 4 million times stronger than a quake of 2.6 magnitude. But comparisons of magnitude don’t tell the whole story.

Northern New Jersey straddles the Ramapo Fault, a significant ancient crack in the earth’s crust. The longest fault in the Northeast, it begins in Pennsylvania and moves into New Jersey, trending northeast through Hunterdon, Somerset, Morris, Passaic, and Bergen counties before terminating in New York’s Westchester County, not far from the Indian Point Energy Center, a nuclear power plant. And though scientists dispute how active this roughly 200 million-year-old fault really is, many earthquakes in the state’s surprisingly varied seismic history are believed to have occurred on or near it. The fault line is visible at ground level and likely extends as deep as nine miles below the surface.

During the past 230 years or so, New Jersey has been at the epicenter of nearly 170 earthquakes, according to data compiled by the New Jersey Geological Survey, part of the United States Department of Environmental Protection. The largest known quake struck in 1783, somewhere west of New York City, perhaps in Sussex County. It’s typically listed as 5.3 in magnitude, though that’s an estimate by seismologists who are quick to point out that the concept of magnitude—measuring the relative size of an earthquake—was not introduced until 1935 by Charles Richter and Beno Gutenberg. Still, for quakes prior to that, scientists are not just guessing.

“We can figure out the damage at the time by going back to old records and newspaper accounts,” says Won-Young Kim, a senior research scientist at Columbia University’s Lamont-Doherty Earth Observatory in Palisades, New York, directly across the New Jersey border. “Once the amount and extent of contemporary damage has been established,” Kim says, “we’re then able to gauge the pattern of ground shaking or intensity of the event—and from there extrapolate its probable magnitude.”

Other earthquakes of magnitude 5 or higher have been felt in New Jersey, although their epicenters laying near New York City. One—which took place in 1737 and was said to have been felt as far north as Boston and as far south as northern Delaware—was probably in the 5 to 5.5 range. In 1884, an earthquake of similar magnitude occurred off New York’s Rockaway Beach. This well-documented event pulled houses off their foundations and caused steeples to topple as far west as Rahway. The shock wave, scientists believe, was felt over 70,000 square miles, from Vermont to Maryland.

Among the largest sub-5 magnitude earthquakes with epicenters in New Jersey, two (a 3.8 and a 4.0) took place on the same day in 1938 in the Lakehurst area in Ocean County. On August 26, 2003, a 3.5 magnitude quake shook the Frenchtown/Milford area in Hunterdon County. On February 3 of last year, a 3.0 magnitude quake occurred in the Morris County town of Mendham. “A lot of people felt this one because of the intense shaking, although the area of intensity wasn’t very wide,” says Lamont-Doherty’s Kim, who visited the site after the event.

After examining the known historical and geological record, Kim and other seismologists have found no clear evidence that an earthquake of greater than 5.3 to 5.5 magnitude has taken place in this area going back to 1737. This doesn’t mean, of course, that one did not take place in the more remote past or that one will not occur in the future; it simply means that a very large quake is less likely to occur here than in other places in the east where the seismic hazard is greater, including areas in South Carolina and northeastern New York State.

Given this low-hazard, high-vulnerability scenario, how far along are scientists in their efforts to predict larger magnitude earthquakes in the New Jersey area? The answer is complex, complicated by the state’s geographical position, its unique geological history, the state of seismology itself, and the continuing debate over the exact nature and activity of the Ramapo Fault.

Over millions of years, New Jersey developed four distinct physiographic provinces or regions, which divide the state into a series of diagonal slices, each with its own terrain, rock type, and geological landforms.

The northernmost slice is the Valley and Ridge, comprising major portions of Sussex and Warren counties. The southernmost slice is the Coastal Plain, a huge expanse that covers some three-fifths of the state, including all of the Shore counties. Dividing the rest of the state are the Highlands, an area for the most part of solid but brittle rock right below the Valley and Ridge, and the lower lands of the Piedmont, which occupy all of Essex, Hudson, and Union counties, most of Bergen, Hunterdon, and Somerset, and parts of Middlesex, Morris, and Passaic.

For earthquake monitors and scientists, the formation of these last two provinces—the Highlands and the Piedmont—are of special interest. To understand why, consider that prior to the appearance of the Atlantic Ocean, today’s Africa was snuggled cozily up against North America and surrounded by a single enormous ocean. “At that point, you could have had exits off the New Jersey Turnpike for Morocco,” says Alexander Gates, professor of geology and chair of the department of Earth and Environmental Sciences at Rutgers-Newark.

Under the pressure of circulating material within the Earth’s super-hot middle layer, or mantle, what was once a single continent—one that is thought to have included today’s other continents as well—began to stretch and eventually break, producing numerous cracks or faults and ultimately separating to form what became the Atlantic Ocean. In our area, the longest and most active of these many cracks was the Ramapo Fault, which, through a process known as normal faulting, caused one side of the earth’s crust to slip lower—the Piedmont—relative to the other side—the Highlands. “All this occurred about 225 million years ago,” says Gates. “Back then, you were talking about thousands of feet between the Highlands and the Piedmont and a very active Ramapo Fault.”

The Earth’s crust, which is 20 to 25 miles thick, is not a single, solid shell, but is broken into seven vast tectonic plates, which drift atop the soft, underlying mantle. Although the northeast-trending Ramapo Fault neatly divides two of New Jersey’s four physiographic provinces, it does not form a so-called plate boundary, as does California’s infamous San Andreas Fault. As many Californians know all too well, this giant fault forms the boundary between two plates—to the west, the Pacific Plate, and to the east, the North American Plate; these rub up against each other, producing huge stresses and a regularly repeating pattern of larger earthquakes.

This second bit of uncertainty is especially troubling for some people, including some in the media who want a neat story. To get around it, they ignore the differences between plate settings and link all of New Jersey’s earthquakes, either directly or implicitly, to the Ramapo Fault. In effect, such people want the Ramapo Fault “to look like the San Andreas Fault,” says Gates. “They want to be able to point to one big fault that’s causing all of our earthquakes.”

Gates does not think that’s the case, and he has been working with colleagues for a number of years to prove it. “What we have found is that there are smaller faults that generally cut from east to west across the northeast-trending Ramapo Fault,” he explains. “These much smaller faults are all over the place, and they’re actually the ones that are the active faults in the area.”

But what mechanisms are responsible for the formation of these apparently active auxiliary faults? One such mechanism, say scientists, is the westward pressure the Atlantic Ocean exerts on the North American Plate, which for the most part resists any movement. “I think we are in an equilibrium state most of the time,” says Lamont-Doherty’s Kim.

Still, that continuous pressure on the plate we sit on causes stress, and when that stress builds up sufficiently, the earth’s crust has a tendency to break around any weak zones. In our area, the major weak zone is the Ramapo Fault—“an ancient zone of weakness,” as Kim calls it. That zone of weakness exacerbates the formation of auxiliary faults, and thereby the series of minor earthquakes the state has experienced over the years.

All this presupposes, of course, that any intraplate stress in this area will continue to be released gradually, in a series of relatively minor earthquakes or releases of energy. But what if that were not the case? What if the stress continued to build up, and the release of large amounts of energy came all at once? In crude terms, that’s part of the story behind the giant earthquakes that rocked what is now New Madrid, Missouri, between 1811 and 1812. Although estimates of their magnitude have been revised downward in recent years to less than magnitude 8, these earthquakes are generally regarded as among the largest intraplate events to have occurred in the continental United States.

For a number of reasons—including the relatively low odds that the kind of stored energy that unleashed the New Madrid events could ever build up here—earthquakes of plus-6 magnitude are probably not in our future. Still, says Kim, even a magnitude 6 earthquake in certain areas of the state could do considerable damage, especially if its intensity or ground shaking was of sufficient strength. In a state as geologically diverse and densely populated as New Jersey, this is a crucial wild card.

Part of the job of the experts at the New Jersey Geological Survey is to assess the seismic hazards in different parts of the state. To do this, they use a computer-simulation model developed under the direction of the Federal Emergency Management Agency, known as HAZUS, for Hazards US. To assess the amount of ground shaking likely to occur in a given county during events ranging in magnitude from 5 to 7 on the Richter Scale, NJGS scientists enter three features of a county’s surface geology into their computer model. Two of these features relate to the tendency of soil in a given area to lose strength, liquefy, or slide downhill when shaken. The third and most crucial feature has to do with the depth and density of the soil itself and the type of bedrock lying below it; this is a key component in determining a region’s susceptibility to ground shaking and, therefore, in estimating the amount of building and structural damage that’s likely to occur in that region. Estimates for the various counties—nine to date have been studied—are sent to the New Jersey Office of Emergency Management, which provided partial funding for the project.

To appreciate why this element of ground geology is so crucial to earthquake modelers, consider the following: An earthquake’s intensity—which is measured on something called the Modified Mercalli Scale—is related to a number of factors. The amount of energy released or the magnitude of an event is clearly a big factor. But two earthquakes of the same magnitude can have very different levels of intensity; in fact, it’s quite possible for a lower magnitude event to generate more ground shaking than a higher magnitude one.

In addition to magnitude, other factors that affect intensity are the distance of the observer or structure from the epicenter, where intensity is the greatest; the depth beneath the surface of the initial rupture, with shallower ruptures producing more ground shaking than deeper ones; and, most significantly, the ground geology or material that the shock wave generated by the earthquake must pass through.

As a rule, softer materials like sand and gravel shake much more intensely than harder materials, because the softer materials are comparatively inefficient energy conductors, so whatever energy is released by the quake tends to be trapped, dispersing much more slowly. (Think of a bowl of Jell-O on a table that’s shaking.)

In contrast, harder materials, like the solid rock found widely in the Highlands, are brittle and break under pressure, but conduct energy well, so that even big shock waves disperse much more rapidly through them, thereby weakening the amount of ground shaking. “If you’ve read any stories about the 1906 earthquake in San Francisco, you know the most intense damage was in those flat, low areas by the Bay, where the soil is soft, and not in the hilly, rocky areas above,” says Karl Muessig, state geologist and NJGS head.

The map that accompanies the online version of the NJGS’s Earthquake Loss Estimation Study divides the state’s surface geology into five seismic soil classes, ranging from Class A, or hard rock, to Class E, or soft soil (state.nj.us/dep/njgs/enviroed/hazus.htm).

Although the weakest soils are scattered throughout the state, including the Highlands, which besides harder rock also contains areas of glacial lakes, clays, and wetlands, they are most evident in the Piedmont and the Coastal Plain. “The largest expanses of them are in coastal areas where you have salt marshes or large glacial lakes, as in parts of the Passaic River basin,” says Scott Stanford, a research scientist with NJGS and lead author of the estimate. Some of the very weakest soils, Stanford adds, are in areas of filled marshland, including places along the Hudson waterfront, around Newark Bay and the Meadowlands, and along the Arthur Kill.

Faults in these areas—and in the coastal plain generally—are far below the ground, perhaps several hundred to a thousand feet down, making identification difficult. “There are numerous faults upon which you might get earthquake movement that we can’t see, because they’re covered by younger sediments,” Stanford says.

This combination of hidden faults and weak soils worries scientists, who are all too aware that parts of the coastal plain and Piedmont are among the most densely populated and developed areas in the state. (The HAZUS computer model also has a “built environment” component, which summarizes, among other things, types of buildings in a given area.) For this reason, such areas would be in the most jeopardy in the event of a large earthquake.

For example, in the study’s loss estimate for Essex County, which includes Newark, the state’s largest city, a magnitude 6 event would result in damage to 81,600 buildings, including almost 10,000 extensively or completely; 36,000 people either displaced from their homes or forced to seek short-term shelter; almost $9 million in economic losses from property damage and business interruption; and close to 3,300 injuries and 50 fatalities. (The New York City Area Consortium for Earthquake Loss Mitigation has conducted a similar assessment for New York City, at nycem.org.)

All of this suggests the central irony of New Jersey geology: The upland areas that are most prone to earthquakes—the counties in or around the Ramapo Fault, which has spawned a network of splays, or auxiliary faults—are much less densely populated and sit, for the most part, on good bedrock. These areas are not invulnerable, certainly, but, by almost all measures, they would not sustain very severe damage, even in the event of a higher magnitude earthquake. The same can’t be said for other parts of the state, where the earthquake hazard is lower but the vulnerability far greater. Here, the best we can do is to prepare—both in terms of better building codes and a constantly improving emergency response.

Meanwhile, scientists like Rutgers’s Gates struggle to understand the Earth’s quirky seismic timetable: “The big thing with earthquakes is that you can commonly predict where they are going to occur,” Gates says. “When they’re going to come, well, we’re nowhere near being able to figure that out.”

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For the men and women of the state police who manage and support the New Jersey Office of Emergency Management (OEM), the response to some events, like hurricanes, can be marshalled in advance. But an earthquake is what responders call a no-notice event.

In New Jersey, even minor earthquakes—like the one that shook parts of Somerset County in February—attract the notice of local, county, and OEM officials, who continuously monitor events around the state from their Regional Operations and Intelligence Center (The ROIC) in West Trenton, a multimillion dollar command-and-control facility that has been built to withstand 125 mph winds and a 5.5 magnitude earthquake. In the event of a very large earthquake, during which local and county resources are apt to become quickly overwhelmed, command and control authority would almost instantly pass to West Trenton.

Here, officials from the state police, representatives of a galaxy of other state agencies, and a variety of communications and other experts would assemble in the cavernous and ultra-high tech Emergency Operations Center to oversee the state’s response. “A high-level earthquake would definitely cause the governor to declare a state of emergency,” says OEM public information officer Nicholas J. Morici. “And once that takes place, our emergency operations plan would be put in motion.”

Emergency officials have modeled that plan—one that can be adapted to any no-notice event, including a terrorist attack—on response methodologies developed by the Federal Emergency Management Agency (FEMA), part of the U.S. Department of Homeland Security. At its core is a series of seventeen emergency support functions, ranging from transportation to firefighting, debris removal, search and rescue, public health, and medical services. A high-magnitude event would likely activate all of these functions, says Morici, along with the human and physical resources needed to carry them out—cranes and heavy trucks for debris removal, fire trucks and teams for firefighting, doctors and EMTs for medical services, buses and personnel carriers for transportation, and so on.

This is where an expert like Tom Rafferty comes in. Rafferty is a Geographic Information Systems Specialist attached to the OEM. His job during an emergency is to keep track electronically of which resources are where in the state, so they can be deployed quickly to where they are needed. “We have a massive database called the Resource Directory Database in which we have geolocated municipal, county, and state assets to a very detailed map of New Jersey,” Rafferty says. “That way, if there is an emergency like an earthquake going on in one area, the emergency managers can quickly say to me, for instance, ‘We have major debris and damage on this spot of the map. Show us the location of the nearest heavy hauler. Show us the next closest location,’ and so on.”

A very large quake, Rafferty says, “could overwhelm resources that we have as a state.” In that event, OEM has the authority to reach out to FEMA for additional resources and assistance. It can also call upon the private sector—the Resource Directory has been expanded to include non-government assets—and to a network of volunteers. “No one has ever said, ‘We don’t want to help,’” Rafferty says. New Jersey officials can also request assistance through the Emergency Management Assistance Compact (EMAC), an agreement among the states to help each other in times of extreme crisis.

“You always plan for the worst,” Rafferty says, “and that way when the worst doesn’t happen, you feel you can handle it if and when it does.”

Contributing editor Wayne J. Guglielmo lives in Mahwah, near the Ramapo Fault.

History Expects the Sixth Seal in NYC (Revelation 6:12)

According to the New York Daily News, Lynn Skyes, lead author of a recent study by seismologists at the Lamont-Doherty Earth Observatory adds that a magnitude-6 quake hits the area about every 670 years, and magnitude-7 every 3,400 years.

A 5.2-magnitude quake shook New York City in 1737 and another of the same severity hit in 1884.

Tremors were felt from Maine to Virginia.

There are several fault lines in the metro area, including one along Manhattan’s 125th St. – which may have generated two small tremors in 1981 and may have been the source of the major 1737 earthquake, says Armbruster.

“The problem here comes from many subtle faults,” explained Skyes after the study was published.

He adds: “We now see there is earthquake activity on them. Each one is small, but when you add them up, they are probably more dangerous than we thought.”

Armbruster says a 5.0-magnitude earthquake today likely would result in casualties and hundreds of millions of dollars in damage.

“I would expect some people to be killed,” he notes.

The scope and scale of damage would multiply exponentially with each additional tick on the Richter scale. (ANI)