Did the earth move for you?
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to stop jumping up and down........
D
dems4me
Guest
elaine said:
When was the last one? Was it here in Maryland? What was it like?
kwillia
n/a
Dear Dems,
To most people in the United States, damaging earthquakes are a California phenomon, but this is misleading. Even though the greatest seismicity in the United States occurs along the Pacific Coast (especially Alaska and Southern California), major earthquakes have also occurred in the central and eastern U.S.
The last earthquake to cause appreciable damage in the eastern United States occurred in 1886 near Charleston, South Carolina. It had an estimated magnitude of 6.5-7, an intensity of X, and was felt over an area of two million square miles. Even in Maryland, the felt intensity from this earthquake was IV to V.
Perhaps the greatest seismic event ever to occur in North America in historic times was a series of earthquakes that shook the mid-continent around New Madrid, Missouri in the winter of 1811-1812. Estimates of the magnitude range as high as 8.7; estimated maximum intensity was XII; and the felt area, which included Maryland, was 2 million square miles.
Other damaging earthquakes in the eastern U.S. include an intensity VIII event near Boston in 1755 and intensity VI events near New York City in 1737 and 1884.
Several earthquakes in adjacent states have been felt in Maryland. Marylanders are more likely to feel one of these out-of-state earthquakes than one within Maryland. As shown by Figure 2, Southwestern Virginia, central Virginia, and the Atlantic seaboard northward from Wilmington, Delaware have significantly more seismic activity than does Maryland. One out-of-state earthquake that was felt in much of Maryland occurred Easter Sunday, April 22, 1984. In fact, it was reported felt in eight states and the District of Columbia, over an area of approximately 19,000 square miles. Centered about 12 miles south of Lancaster, Pennsylvania, this earthquake registered 4.1 on the Richter Scale and had an epicentral intensity of V to VI. Most notable effects in Maryland were in the northeastern part of the state, which generally experienced Modified Mercalli Intensity V effects for example, hanging pictures fell in Conowingo; windows cracked in Elkton and Joppa; and standing vehicles rocked slightly in Union Bridge (Stover, 1988). A 3.0-magnitude tremor four days earlier is considered to have been a foreshock. Ten aftershocks registering 2 to 2.5 Richter magnitude occurred over a four-day period after the April 22 event. The Lancaster earthquake is likely related to Triassic-age structures in the area.
As of late 1993, 47 earthquakes had been reported within Maryland’s borders. Over the next ten years, that total reached 61. The accuracy and precision of these epicenter determinations is such that a few of the closer out-of-state earthquakes could have occurred within Maryland and some of those near the state’s boundaries may actually have occurred in adjacent states. For example, not included in the list was a moderate shock that occurred on January 2, 1885 in an area near the Frederick County, Maryland-Loudon County, Virginia border. The maximum intensity was V, with the total felt area covering more than 3,500 square miles. Of the Maryland earthquakes, 2 occurred in the Valley and Ridge Province, 36 were in the Piedmont Province, and 10 were in the Coastal Plain Province.
The first reported earthquake to have actually had its epicenter in Maryland occurred south of Annapolis on April 25, 1758, but no record of its strength is known to exist. The shock lasted 30 seconds and was preceded by subterranean noises. Additional felt reports were received from a few points in Pennsylvania (U.S. Geological Survey, 1973). Maryland's strongest confirmed tremor was a 3.1-magnitude event near Hancock, Washington County, in 1978. That perhaps was rivaled by an intensity V event (unknown magnitude) near Phoenix, Baltimore County, in 1939. Earthquakes of such magnitudes or intensities are still considered to be minor, and very seldom result in significant damage or injury.
Sincerely,
kwillia
To most people in the United States, damaging earthquakes are a California phenomon, but this is misleading. Even though the greatest seismicity in the United States occurs along the Pacific Coast (especially Alaska and Southern California), major earthquakes have also occurred in the central and eastern U.S.
The last earthquake to cause appreciable damage in the eastern United States occurred in 1886 near Charleston, South Carolina. It had an estimated magnitude of 6.5-7, an intensity of X, and was felt over an area of two million square miles. Even in Maryland, the felt intensity from this earthquake was IV to V.
Perhaps the greatest seismic event ever to occur in North America in historic times was a series of earthquakes that shook the mid-continent around New Madrid, Missouri in the winter of 1811-1812. Estimates of the magnitude range as high as 8.7; estimated maximum intensity was XII; and the felt area, which included Maryland, was 2 million square miles.
Other damaging earthquakes in the eastern U.S. include an intensity VIII event near Boston in 1755 and intensity VI events near New York City in 1737 and 1884.
Several earthquakes in adjacent states have been felt in Maryland. Marylanders are more likely to feel one of these out-of-state earthquakes than one within Maryland. As shown by Figure 2, Southwestern Virginia, central Virginia, and the Atlantic seaboard northward from Wilmington, Delaware have significantly more seismic activity than does Maryland. One out-of-state earthquake that was felt in much of Maryland occurred Easter Sunday, April 22, 1984. In fact, it was reported felt in eight states and the District of Columbia, over an area of approximately 19,000 square miles. Centered about 12 miles south of Lancaster, Pennsylvania, this earthquake registered 4.1 on the Richter Scale and had an epicentral intensity of V to VI. Most notable effects in Maryland were in the northeastern part of the state, which generally experienced Modified Mercalli Intensity V effects for example, hanging pictures fell in Conowingo; windows cracked in Elkton and Joppa; and standing vehicles rocked slightly in Union Bridge (Stover, 1988). A 3.0-magnitude tremor four days earlier is considered to have been a foreshock. Ten aftershocks registering 2 to 2.5 Richter magnitude occurred over a four-day period after the April 22 event. The Lancaster earthquake is likely related to Triassic-age structures in the area.
As of late 1993, 47 earthquakes had been reported within Maryland’s borders. Over the next ten years, that total reached 61. The accuracy and precision of these epicenter determinations is such that a few of the closer out-of-state earthquakes could have occurred within Maryland and some of those near the state’s boundaries may actually have occurred in adjacent states. For example, not included in the list was a moderate shock that occurred on January 2, 1885 in an area near the Frederick County, Maryland-Loudon County, Virginia border. The maximum intensity was V, with the total felt area covering more than 3,500 square miles. Of the Maryland earthquakes, 2 occurred in the Valley and Ridge Province, 36 were in the Piedmont Province, and 10 were in the Coastal Plain Province.
The first reported earthquake to have actually had its epicenter in Maryland occurred south of Annapolis on April 25, 1758, but no record of its strength is known to exist. The shock lasted 30 seconds and was preceded by subterranean noises. Additional felt reports were received from a few points in Pennsylvania (U.S. Geological Survey, 1973). Maryland's strongest confirmed tremor was a 3.1-magnitude event near Hancock, Washington County, in 1978. That perhaps was rivaled by an intensity V event (unknown magnitude) near Phoenix, Baltimore County, in 1939. Earthquakes of such magnitudes or intensities are still considered to be minor, and very seldom result in significant damage or injury.
Sincerely,
kwillia
D
dems4me
Guest
Ehesef said:
try to stop ridding my azz you ankle-bitting buttmunch ... the artice also stated that "Quakes of magnitude 2.5 to 3 are generally the smallest that can be felt."
As for our area -- in 2001 there was a 2.0 and the largest was a 2.7 in 1993 - I was hoping that Elaine could give us some insight on a larger quake, perhaps she spent time in California or something.
D
dems4me
Guest
kwillia said:
Thanks
First the doom and gloom snow forecast and now earthquakes -- it all has me in quite a quandary 
kwillia
n/a
Compared with other States, Maryland ranks number 33 for frequency of Tornadoes, 37 for number of deaths, 33 for injuries and 35 for cost of damages. When we compare these statistics to other States by the frequency per square mile, Maryland ranks, number 15 for the frequency of tornadoes, number 30 for fatalities, number 28 for injuries per area and number 27 for costs per area. Based on data from 1950 - 1995.dems4me said:Thanks
Maryland in 1970 had a population of 3,923,897 and between 1950 and 1995 had 169 tornadoes. This ranks the State number 33 in tornadoes by State. The population in 1970 divided by the number of tornadoes equals 23,218 This ranks Maryland number 39 in the ratio of tornadoes to population. Maryland had 2 fatalities between 1950 and 1995. Compared to other states it ranked 37 The risk of death in any one year is 1 in 88,287,683 This ranks Maryland as number 39 for the risk of death by tornado . Between 1950 and 1995 the state had 122 injuries involving tornadoes. This ranks the state number 33 among the States for injury. The risk of injury in any one year is one in 1,447,339 When we divide the population by the number of injuries, the State ranks number 39 The total cost of tornadoes between 1950 and 1995 was $41,411,360.00.
Ehesef
Yo Gabba Gabba
You have some sort of anger management issue. I just suggested that you read the article to find the information that you asked about.dems4me said:try to stop ridding my azz you ankle-bitting buttmunch ... the artice also stated that "Quakes of magnitude 2.5 to 3 are generally the smallest that can be felt."
As for our area -- in 2001 there was a 2.0 and the largest was a 2.7 in 1993 - I was hoping that Elaine could give us some insight on a larger quake, perhaps she spent time in California or something.
D
dems4me
Guest
kwillia said:
Wow thanks!!! I was living in LaPlata at the time the tornado hit... one of the scariest experiences I have lived through. Any stats for somd snowstorms?
D
dems4me
Guest
Ehesef said:
I did read the article azzhole.
D
dems4me
Guest
aps45819 said:
Good - things can only go up from here...
D
dems4me
Guest
Ehesef said:Man. you've really got your knickers in a knot today, don't you? Do you need a
Get your red back-stabing hands off my neck!!!
