Posted on 01/02/2009 1:09:38 PM PST by Red Badger
A meteorite impact off Long Island 2,300 years ago may have set off a huge tsunami that flooded the New York City region, a new study says (New York City and Long Island map).
It's not known whether any ancient settlements were in the path of the proposed killer waves, but "any significant tsunami today would be devastating and likely to flood places like lower Manhattan," Vanderbilt University geologist Steven Goodbred said.
Tsunamis are typically triggered by seismic events. An undersea earthquake, for example, caused the catastrophic 2004 Indian Ocean tsunami. But meteorite strikes have also been known to spark the killer waves.
In the New York area, "there are no exploding volcanoes and there probably haven't been" for millions of years, said study co-author Katherine Cagen of Harvard University. "The same goes for [major] earthquakes."
Cagen, however, recently found signs of a meteorite impact in sediments taken from several sites along the Hudson River, which forms the border between New York City and New Jersey.
The evidence included deformed rocks; rare microscopic "nanodiamonds"; and microscopic, perfectly round rocks called spherules, which form when molten and vaporized rock are flung into the air by a space impact and then solidify in the temporary vacuum created by the blast.
Nothing as big as a crater has been found, but Dallas Abbott, a Columbia University impact expert, estimates that the space rock would have had a diameter of between about 165 feet (50 meters) and 490 feet (150 meters). Any smaller, and a major wave would not have formed and the rock would have exploded before hitting Earth. Any bigger, and the strike would have created "impact glass"—forged in the extreme heat of an impact blast—which has not been found as of yet.
Abbott presented her team's research this month at the annual meeting of the American Geophysical Union in San Francisco.
Mystery Solved?
The Hudson River samples date back to around 300 B.C.—the same age as some out-of-place gravel deposits discovered by another team of scientists on Long Island in 2003.
The rocky layer is several inches thick and appears to have been transported from a gravel-rich coast a few hundred meters away. The individual rocks are quite large—some as big as fists—so normal waves or wind could not have carried the stones, according to Vanderbilt's Goodbred.
At the time of the gravel discovery, Goodbred suggested that the rocks had been moved by one of two phenomena: a very big storm or a tsunami.
The new meteorite evidence may tip the scales toward the tsunami theory. Even so, Goodbred stressed that the research is still in its early stages.
"There are two unique hypotheses here"—the tsunami and the storm—"and either one or both may yet be proven incorrect," he said.
Geologist Ted Bryant of the University of Wollongong in Australia said an extraterrestrial impact is the most likely explanation for the spherules and nanodiamonds.
Abbott's "discoveries cannot be reproduced by processes naturally occurring in the New York region," said Bryant, who was not involved in the new study.
"Is her hypothesis wild? No. Is it unconventional? Yes," he added. "But so was continental drift when it was first proposed."
Microscopic carbon spherules found in sediments along the Hudson River were likely formed in a meteorite blast 2,300 years ago, scientists announced in December 2008. The discovery adds to evidence of an ancient tsunami that, if it occurred today, would flood lower Manhattan.
Ping!........
I won’t say it. I’ll sure as hell THINK it, but I won’t say it.
What?...............
Isn’t it great how these scientists come up with a theory and present it as fact about an occurrence 2300 years ago, It must be great to be right all the time.
And Yes, I had to look twice too.
A tsunami didn’t hit New York City in 2008? Unfortunately, it then went all the way to the left coast and scraped everything in between. I’m still waiting for the seiche.
There was a worldwide tree-ring event in 207BC.
The Chinese Han Dynasty began at this time too.
My thoughts exactly..except to say: "Apophis"
thanks!
Meteorite Strikes, Setting Off a Tsunami: Did It Happen Here?[NY]
NY Times | 29 Dec 2008 | Kenneth Chang
Posted on 12/31/2008 2:26:04 PM PST by BGHater
http://www.freerepublic.com/focus/f-chat/2156947/posts
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Rain of Iron and IceOn November 27,1919, a meteorite fell into Lake Michigan near the Michigan shore. "Residents of Battle Creek, Kalamazoo, South Bend, Grand Haven, and other Western Michigan cities fled from their homes in panic, fearing an earthquake. Houses were shaken, the country was illuminated as by a bright sun's rays, so all-enveloping it was impossible to tell from which direction the flare came, the earth trembled for half a moment and then came a deep prolonged rumbling as of a terrific explosion." (p 159)
by John S. Lewis
A disaster in The Han is worth two in the Bush?.......
A hushed 'ahem.'
Note: this topic is from 1/02/2009. Thanks Red Badger.
Maybe history will repeat itself.....................
Just an updated ping message.
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