November — A quake 90 miles north of Quebec City in eastern Canada registered magnitude 6. April — A quake registering between magnitude 2. It lasted just five seconds and caused no damage. January — Two small earthquakes struck the area surrounding Hastings-on-Hudson.
One was a magnitude of 1. March — Two earthquakes struck Rockland. The first, at 1. Geological Survey site shows the Ramapo seismic zone as currently being active with many mini earthquakes, usually ranging below 1 up to 4.
The Ramapo fault zone is not the only earthquake-prone area in Pennsylvania, as an active PA earthquake fault line in Erie, Pennsylvania, was responsible for the 5. At least 90 percent of all earthquake activity in the world occurs along the continents that border the Pacific Ocean, nicknamed the Ring of Fire.
This area also serves as home to 75 percent of the world's volcanoes. The world's largest exposed fault line called the Banda Detachment — recently discovered along the Ring of Fire off the coast of eastern Indonesia in the Banda Sea on the Ring of Fire — exposes a fault plane on the sea floor that covers over 23, square miles and runs just over 4 miles deep.
A fault line occurs where tectonic plates or boundaries meet. With three geological boundary types — divergent, transform and convergent — three basic types of faults define the activity that occurs where these boundaries meet. These faults include the strike-slip fault typically found along transform boundaries in which both plates slide horizontally, normal faults occur along divergent boundaries where one side of the boundary drops below another, and the thrust fault where one side thrusts up instead of down.
Many earthquakes zones include faults that consist of combinations of these fault types like the San Andreas fault zone that is 95 percent strike-slip and 5 percent reverse or thrust fault.
As a journalist and editor for several years, Laurie Brenner has covered many topics in her writings, but science is one of her first loves.
Her stint as Manager of the California State Mining and Mineral Museum in California's gold country served to deepen her interest in science which she now fulfills by writing for online science websites.
Brenner is also a published sci-fi author. She graduated from San Diego's Coleman College in Plates are the masses of the earth's crust that slowly move, maybe as little as a few centimeters a year to as much 18 centimeters, around the globe.
Faults such as the San Andreas are interplate and occur near where two plates meet. The theory is that as plates interact with one another, they create stress within the plate. Faults occur where the crust is weak, Gates said. Earthquakes relieve the built up pressure. Boston College Geophysics Professor John Ebel said he and a Virginia Tech colleague, believe the seismically active areas in New York and South Carolina are where some million years ago, the plates tried to break off but failed.
This led to a weakening of the earth's crust which makes them susceptible to quakes. While not predictable, the data collected seem to suggest earthquakes occur somewhat periodically, 40 active years followed by 40 less active, Gates said.
It would shake the area. Everybody would be upset. Ebel does not fully agree. He said saying "overdue" might be somewhat misleading. Earthquakes happen through a slow process of rising stress, "like dropping individual grains of sand on the table. Still all three experts say statistically it is only a matter time before a magnitude 5 quake is recorded in the northern New Jersey area. The scientists said quakes in the Northeastern part of the United States tend to come years apart and the last one was recorded in believed to be centered south of Brooklyn.
It toppled chimneys and moved houses from their foundations across the city and as far as Rahway. Washington D.
That quake cracked the Washington Monument. And having only a partial year history, we may not have seen everything we could see. There could be surprises — things bigger than we have ever seen," Armbruster wrote.
The Earth Institute's article did note New York City added earthquake-resistant building codes in New Jersey also began to require earthquake-resistant standards in the s. The state, following the Virginia quake, now requires lake communities to make dams able to withstand a magnitude 5 earthquake.
0コメント