Earthquake Hits Akwesasne

Shortly after midnight on November 28, 2015, Akwesasne and most of the North Country felt a minor earthquake, minor but enough to rattle and shake most homes. According to the United States Geological Survey, the earthquake measured 3.2 on the Richter scale. There are two ways in which scientists quantify the size of earthquakes: magnitude and intensity. Magnitude is a measure of the amount of energy released during an earthquake. The Richter scale does not measure large earthquakes very well, especially if the seismometers used are very far away from an earthquake epicenter. The moment magnitude scale is now most commonly used for medium to large earthquakes.

Dr. Charles Richter, a seismologist at the California Institute of Technology, invented the Richter scale in the 1930s. It is a measure of the largest seismic wave recorded on a particular kind of seismograph located 100 kilometers (about 62 miles) from the epicenter of the earthquake.

On Saturday, November 28, 2015, at least 17 earthquakes were reported, according to the USGS, up to 50 earthquakes can happen in a 24 period without cause for alarm, or being noted as unusual. Several earthquakes were reported in Oklahoma, California, Oregon and Kansas, as well as Puerto Rico, Mexico and the Virgin Islands. All were considered minor with no reports of significant damage and the largest earthquake felt was in Sardinal, Costa Rica at 4.9 on Saturday.

Specific Details of "Our" earthquake;

M3.2 - 2km SSE of Cornwall, Canada

Time

2015-11-28 05:16:54 (UTC)

2015-11-28 00:16:54 (UTC-05:00) in your timezone

Nearby Cities

4km (2mi) S of Cornwall, Canada

13km (8mi) ENE of Massena, New York

51km (32mi) SW of Les Coteaux, Canada

55km (34mi) WSW of Salaberry-de-Valleyfield, Canada

89km (55mi) ESE of Ottawa, Canada

Earthquakes in the Adirondack Region

The Adirondack region of northern New York State is one of the more seismically active parts of the northeastern U.S. The three largest known earthquakes in the region caused about $20 million of damage (in 2002 dollars) to Cornwall, Ontario, and to Massena, New York in 1944 (magnitude 5.8), caused slight damage in a sparsely settled part of the southern Adirondack Mountains in 1983 (magnitude 4.9), and damaged the vicinity of Plattsburgh, New York, on April 20, 2002 (magnitude 5.0). Moderately damaging earthquakes strike somewhere in the region every few decades, and smaller earthquakes are felt about once every three or four years.

Earthquakes in the central and eastern U.S., although less frequent than in the western U.S., are typically felt over a much broader region. East of the Rockies, an earthquake can be felt over an area as much as ten times larger than a similar magnitude earthquake on the west coast. A magnitude 4.0 eastern U.S., earthquake typically can be felt at many places as far as 100 km (60 mi) from where it occurred, and it infrequently causes damage near its source. A magnitude 5.5 eastern U.S. earthquake usually can be felt as far as 500 km (300 mi) from where it occurred, and sometimes causes damage as far away as 40 km (25 mi).

Faults

Earthquakes everywhere occur on faults within bedrock, usually miles deep. Most of the Adirondack region's bedrock was formed as several generations of mountains rose and were eroded down again over the last billion or so years.

Often scientists can determine the name of the specific fault that is responsible for an earthquake, such as the well-studied plate like the San Andreas fault system in California, In contrast, east of the Rocky Mountains this is rarely the case. The Adirondack region is far from the nearest plate boundaries, which are in the center of the Atlantic Ocean and in the Caribbean Sea. The region is laced with known faults but numerous smaller or deeply buried faults remain undetected. Even the known faults are poorly located at earthquake depths. Accordingly, few Adirondack earthquakes can be linked to named faults. It is difficult to determine if a known fault is still active and could slip and cause an earthquake. As in most other areas east of the Rockies, the best guide to earthquake hazards in the Adirondack region is the earthquakes themselves.

Earthquake History

Throughout the North Country and surrounding areas;

Earthquakes were reported in 1638, 1638, 1661, 1663, and 1732 in the St. Lawrence Valley.

December 18, 1737 - An earthquake was felt near New York City and in Buffalo.

October 23, 1857 - A rather severe earthquake centered in northeastern New York caused moderate damage along the St. Lawrence River and in the Lake Champlain area in 1877.

August 10, 1884 - An earthquake caused large cracks in walls at Amityville and Jamaica.

May 27, 1897 - A shock reported as severe, but with no damage noted occurred in northeastern New York. It was felt over the greater portion of New York and parts of adjacent New England States and Quebec, Canada.

February 28, 1925 - A very large area of the northeastern United States and eastern Canada, about 4,200,000 square kilometers, was shaken by a magnitude 7 earthquake. A maximum intensity of VIII was reached in the epicentral region, near La Malbaie, Quebec, Canada. A large portion of New York State experienced intensity IV effects; lesser intensities were noted south of Albany.

August 12, 1929 - Extensive damage occurred in the Attica area from a strong shock.

April 20, 1931 - An earthquake was reported centering near Lake George.

November 1, 1935 - The magnitude 6 1/4 earthquake centered near Timiskaming, Quebec, Canada, caused slight damaged at many points in New York.

September 4, 1944 - An earthquake centered about midway between Massena, New York, and Cornwall, Ontario, Canada, caused an estimated $2,000,000 damage in the two cities. The shock destroyed or damaged about 90 percent of the chimneys at Massena, with similar effects at Cornwall. In addition, masonry, plumbing, and house foundations were damaged at Massena. Many structures were rendered unsafe for occupancy. Press reports indicated a large number of wells in St. Lawrence County went dry, causing acute hardship. Brick masonry and concrete structures were damaged at Hogansburg; some ground cracking was also noted at nearby towns. This earthquake was felt over approximately 450,000 square kilometers in the United States, including all the New England States, Delaware, Maryland, New Jersey, Pennsylvania, and portions of Michigan and Ohio. A few points in Illinois, Indiana, Virginia, West Virginia, and Wisconsin also reported feeling the tremor.

January 1, 1966 - A magnitude 4.7 disturbance on, causing slight damage to chimneys and walls at Attica and Varysburg. Plaster fell at the Attica State Prison and the main smokestack was damaged. The total felt area was about 46,500 square kilometers.

Sources; New Mexico Bureau of Geology & Mineral Resources, United States Geological Survey, Wikipedia