April 9, 2019– Mary Greeley News – Toady according to the USGS there was a M3.0 earthquake off the Coast of New York.
It had a depth of 7km or 4.3 miles, 168 km (104 miles) E of Brooklyn, United States. It occulted a 7:22 AM local time. 64 km(39 miles) SE of Southampton near the Long Island Sound.
The city of 8.5 million people is not thought of as a tremor hot spot, but the five boroughs are riddled with fault lines that could bring dozens of buildings down.
New York City could be hit with a $39 billion in damage with 30 million tons of debris clogging the streets if a long-overdue earthquake hit.
Because the city is so dense and littered with thousands of tall buildings, even a 5.0 magnitude earthquake nearby would cause such damage, experts fear.
New York, which is actually riddled with faults, has a long history of earthquakes: On average, the region has witnessed a moderate quake (about a 5.0 on the Richter scale) every hundred years. The last one was in 1884. Seismologists say we can expect the next one any day now.
Admittedly, a moderate quake isn’t going to cause Hollywood-level destruction, nor is it going to raze Manhattan. But it is going to do plenty of damage: upwards of $39 billion in losses and over 30 million tons of debris. That rubble, caused largely by crumbled brick and stone buildings, is going to clog already congested roads, making it impossible for first responders and public transportation to move about the city.
It may be equally difficult to travel below ground in some cases. Take the Steinway Tunnel, a 1.3-mile cast-iron tube that runs deep below the East River. The 7 train passes through it every 20 minutes, often packed with commuters or, this time of year, Mets fans. Construction on the tunnel began around the time of the last earthquake, long before seismic codes or even modern engineering practices had been codified.
As a result, there are big craters and gaps where the tunnel lining isn’t in contact with the earth around it. In the event of a quake, that’s going to cause the tunnel to rattle around.
And because the tunnel runs through both the soft mud of the riverbed and the hard bedrock on either side, different segments are going to rattle around at different speeds and frequencies. That’s doubly bad news for cast iron that was never in very good shape to begin with.
Those faults that crisscross Manhattan are not the only ones capable of seismic activity. Geologists now believe that the Ramapo Fault, which spans 185 miles from the Hudson Highlands through New Jersey and Pennsylvania, may be capable of a much stronger earthquake — maybe even one as strong as a 7.0.
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.
That kind of quake could easily do more damage to the city proper than 9/11 or Superstorm Sandy. And given the fault’s proximity to Indian Point Energy Center, Entergy’s beleaguered nuclear power plant in Westchester County, crumpled brownstones and inactive subway tunnels may be the least of our concerns.
A few years ago, the United States Geological Survey conducted a seismic-risk assessment of all nuclear power plants.
Excluding a few plants on the West Coast, Indian Point was deemed the plant with the greatest risk of core damage as a result of seismic activity, a dubious distinction for sure.
After the Fukushima disaster in Japan in 2011, the US Nuclear Regulatory Commission required all US plants to undergo an extensive seismic evaluation, with an eye toward instituting additional safeguards and retrofits. Entergy was to submit its evaluation of Indian Point this year. Not only has it failed to do so, but it has made a formal request of the NRC that this requirement be waived altogether, citing the closure of the plant in 2021 as justification for this waiver.
Just how well the plant would perform in an earthquake remains a subject of debate among scientists and engineers.
Klaus Jacob, a research scientist at Columbia’s Lamont-Doherty Earth Observatory, thinks even a 5.0 quake would raise safety concerns at the plant. A 7.0, he says, could easily do damage to the domes containing the reactors.
Meanwhile, the siting of a large natural-gas pipeline near the plant has raised concerns with some nuclear insiders, who predict an explosion could create a Fukushima-like event there. Gas pipelines aren’t held to the same seismic standards as power plants, and they aren’t required to survive a seismic event. They also come with some of the same vulnerabilities seen in tunnels like the Steinway.
Were this pipeline to rupture in an earthquake, it could cause a meltdown easily capable of billions of dollars in damage and the evacuation of millions of people.
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.
In January, a 4.7 magnitude earthquake was recorded Tuesday evening off the coast of Ocean City, Md., but the effects rippled through several states including New York.
The U.S. Geological Survey said the quake was at a depth of 10 kilometers, or 6.2 miles, about 136 miles off the coastline, and happened around 6:30 p.m.
credit: In part with https://en.m.wikipedia.org/wiki/Earthquake_activity_in_the_New_York_City_area