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1975 Near Islands Earthquake
The 1975 Near Islands earthquake occurred at 08:43 UTC on February 2 off the coast of Attu Island, Alaska. The earthquake had a surface-wave magnitude of 7.6 and a maximum Mercalli intensity of IX (''Violent''). It caused heavy damage on Shemya Island, injuring 15 residents. The runways of Shemya Air Force Base sustained cracks up to wide, and crevices with as much as of displacement were observed on the island. See also * List of earthquakes in 1975 * List of earthquakes in Alaska *List of earthquakes in the United States *Near Islands References External links * Rat Islands The Rat Islands (,) are a group of American High islands, volcanic islands in the Aleutian Islands in southwestern Alaska, between Buldir Island and the Near Islands group to its west, and Amchitka Pass and the Andreanof Islands group to its e ... 1975 in Alaska Earthquakes in the Aleutian Islands Near Islands {{Earthquake-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alaska
Alaska ( ) is a non-contiguous U.S. state on the northwest extremity of North America. Part of the Western United States region, it is one of the two non-contiguous U.S. states, alongside Hawaii. Alaska is also considered to be the northernmost, westernmost, and easternmost (the Aleutian Islands cross the 180th meridian into the eastern hemisphere) state in the United States. It borders the Canadian territory of Yukon and the province of British Columbia to the east. It shares a western maritime border, in the Bering Strait, with Russia's Chukotka Autonomous Okrug. The Chukchi and Beaufort Seas of the Arctic Ocean lie to the north, and the Pacific Ocean lies to the south. Technically, it is a semi-exclave of the U.S., and is the largest exclave in the world. Alaska is the largest U.S. state by area, comprising more total area than the following three largest states of Texas, California, and Montana combined, and is the seventh-largest subnational division i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Attu Island
Attu (, ) is an island in the Near Islands (part of the Aleutian Islands chain). It is one of the westernmost points of the U.S. state of Alaska. The island became uninhabited in 2010, making it the largest uninhabited island that is part of the United States politically. (archived June 25, 2017) In the chain of the Aleutians, the islands immediately to the west of Attu are the Russian Commander Islands, away (and on the other side of the International Date Line). Attu is nearly from the Alaskan mainland and northeast of the northernmost of the Kuril Islands of Russia, as well as being from Anchorage, from Alaska's capital of Juneau, and from New York City. Attu is about in size with a land area of , making it #23 on the list of largest islands in the United States. Attu Station, a former Coast Guard LORAN station, is located at , making it one of the westernmost points of the United States relative to the rest of the country. (Technically it is in the Eastern Hemisph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Surface-wave Magnitude
The surface wave magnitude (M_s) scale is one of the magnitude scales used in seismology to describe the size of an earthquake. It is based on measurements of Rayleigh surface waves that travel along the uppermost layers of the Earth. This magnitude scale is related to the local magnitude scale proposed by Charles Francis Richter in 1935, with modifications from both Richter and Beno Gutenberg throughout the 1940s and 1950s. It is currently used in People's Republic of China as a national standard (GB 17740-1999) for categorising earthquakes. Recorded magnitudes of earthquakes through the mid 20th century, commonly attributed to Richter, could be either M_s or M_L. Definition The formula to calculate surface wave magnitude is: :M_s = \log_\left(\frac\right)_ + \sigma(\Delta)\,, where A is the maximum particle displacement in surface waves (vector sum of the two horizontal displacements) in μm, T is the corresponding period in s (usually 20 2 seconds), Δ is the e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shemya Island
Shemya or Simiya () is a small island in the Semichi Islands group of the Near Islands chain in the Aleutian Islands archipelago southwest of Alaska, at . It has a land area of , and is about southwest of Anchorage, Alaska. It is wide and long. History The Russian vessel ''Saint Peter and Paul'' wrecked at Shemya in 1762. Most of the crew survived. In 1943, a United States Air Force radar surveillance, weather station, aircraft refueling station, and a runway opened on Shemya and are still in operation. At its peak in the 1960s, the station, originally Shemya Air Force Base or Shemya Station, had 1,500 workers. In 1956, Northwest Airlines leased Shemya Island from the U.S. government to use as a refueling station on their North Pacific route. According to Northwest's website, that made them "the first airline to operate its own airport." Northwest was operating Lockheed Constellation Lockheed L-1049 Super Constellation, L-1049G model propliners on its "Orient Express" servic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shemya Air Force Base
Eareckson Air Station , formerly Shemya Air Force Base, is a United States Air Force military airport located on the island of Shemya, in the Alaskan Aleutian Islands. The airport was closed as an active Air Force Station on 1 July 1994. However, it is still owned by the USAF and is operated by the USAF Pacific Air Forces Regional Support Center at Elmendorf AFB for refueling purposes. It also serves as a diversion airport for civilian aircraft. The base previously hosted the AN/FPS-17 and AN/FPS-80 radars and since 1977 the more powerful AN/FPS-108 COBRA DANE phased-array radar. Overview Eareckson Air Station is located on the western tip of Alaska's Aleutian islands near the larger island of Attu, lying approximately 1,500 miles southwest of Anchorage. The airport lies on the south side of the 2-mile by 4-mile island and is 98 feet above mean sea level. Shemya Island has been the scene of two major earthquakes. The 1965 Rat Islands earthquake, measuring 8.7 on the moment m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Earthquakes In 1975
This is a list of earthquakes in 1975. Only earthquakes of magnitude 6 or above are included, unless they result in damage and/or casualties, or are notable for some other reason. All dates are listed according to UTC time. Maximum intensities are indicated on the Mercalli intensity scale and are sourced from United States Geological Survey (USGS) ShakeMap data. The year was characterized by several large events which helped bring the number of magnitude 7.0+ events to 13. Six events were larger than the biggest event of 1974. Two events reached magnitude 7.9. Turkey had the deadliest event with 2,300 lives being lost in September. China had an earthquake in February which resulted in 2,000 deaths. By death toll Listed are earthquakes with at least 10 dead. By magnitude Listed are earthquakes with at least 7.0 magnitude. By month January February March April May June July August September October November December ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Earthquakes In Alaska ...
This is an incomplete list of earthquakes in Alaska. See also * Geology of Alaska References {{Authority control Earthquakes Alaska Earthquakes An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Earthquakes In The United States
The following is a list of notable earthquakes and tsunamis which had their epicenter in areas that are now part of the United States with the latter affecting areas of the United States. Those in ''italics'' were not part of the United States when the event occurred. List of earthquakes Earthquake swarms which affected the United States: * 1962–71 Denver earthquake swarm * Enola earthquake swarm * 2008 Reno earthquakes * Guy-Greenbrier earthquake swarm * Oklahoma earthquake swarms (2009–present) Earthquakes which affected the United States but whose epicenters were outside the United States borders: * 1925 Charlevoix–Kamouraska earthquake – magnitude 6.2 earthquake, no injuries or fatalities anywhere * 1979 Imperial Valley earthquake – magnitude 6.4 earthquake with an epicenter less than 1 km inside Mexico – significant damage and injuries on both sides of the border (60 in the US) * 2010 Baja California earthquake (Mexico near S California) – magnitu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Near Islands
The Near Islands or the Sasignan Islands (, ) are a group of volcanic islands in the Aleutian Islands in southwestern Alaska, between the Russian Commander Islands to the west and Buldir Island and the Rat Islands to the east. Geography The largest of the Near Islands are Attu Island, Attu and Agattu, which shelter a few islet, rocks in the channel between them. The other important islands are the Semichi Islands to their northeast, notable among which are Alaid Island (Alaska), Alaid, Nizki Island, Nizki, and Shemya Island, Shemya. About to the east-southeast from Shemya are small rocky reefs known as the Ingenstrem Rocks. The total land area of all of the Near Islands is 1,143.785 km2 (441.618 sq mi), and their total population was 47 persons as of the 2000 United States census, 2000 census. The only populated island is Shemya; the Attu Station, Alaska, U.S. Coast Guard station on Attu closed in 2010 and all inhabitants left the island later that year. On July 17, 2017 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1975 Earthquakes
It was also declared the ''International Women's Year'' by the United Nations and the European Architectural Heritage Year by the Council of Europe. Events January * January 1 – Watergate scandal (United States): John N. Mitchell, H. R. Haldeman and John Ehrlichman are found guilty of the Watergate cover-up. * January 2 ** The Federal Rules of Evidence are approved by the United States Congress. ** A bomb blast at Samastipur, Bihar, India, fatally wounds Lalit Narayan Mishra, Minister of Railways. * January 5 – Tasman Bridge disaster: The Tasman Bridge in Hobart, Tasmania, Australia, is struck by the bulk ore carrier , causing a partial collapse resulting in 12 deaths. * January 15 – Alvor Agreement: Portugal announces that it will grant independence to Angola on November 11. * January 20 ** In Hanoi, North Vietnam, the Politburo approves the final military offensive against South Vietnam. ** Work is abandoned on the 1974 Anglo-French Channel Tunnel scheme. * January ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earthquakes In The Aleutian Islands
An earthquakealso called a quake, tremor, or tembloris the shaking of the Earth's surface resulting from a sudden release of energy in the lithosphere that creates seismic waves. Earthquakes can range in intensity, from those so weak they cannot be felt, to those violent enough to propel objects and people into the air, damage critical infrastructure, and wreak destruction across entire cities. The seismic activity of an area is the frequency, type, and size of earthquakes experienced over a particular time. The seismicity at a particular location in the Earth is the average rate of seismic energy release per unit volume. In its most general sense, the word ''earthquake'' is used to describe any seismic event that generates seismic waves. Earthquakes can occur naturally or be induced by human activities, such as mining, fracking, and nuclear weapons testing. The initial point of rupture is called the hypocenter or focus, while the ground level directly above it is the epicen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
