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2018 Anchorage Earthquake
On November 30, 2018, at 8:29 a.m. AKST (17:29 UTC), a magnitude 7.1 earthquake hit Anchorage in Southcentral Alaska. The earthquake's epicenter was near Point Mackenzie, about north of Anchorage, and occurred at a depth of . It was followed six minutes later by a magnitude 5.7 aftershock centered north-northwest of the municipality. The earthquake could be felt as far away as Fairbanks. The National Tsunami Warning Center—itself located inside the quake zone, in Palmer, Alaska, northeast of Anchorage—issued tsunami warnings for nearby coastal areas, including Cook Inlet and the Kenai Peninsula, but they were lifted shortly after. Tectonic setting Southern Alaska lies at the eastern end of the Aleutian Trench, where the Pacific plate is subducting beneath the North American plate. Near Anchorage, the plates are converging at a rate of 57 mm per year. The region has experienced severe earthquakes in the past, including several megathrust earthquakes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glenn Highway
The Glenn Highway (part of Alaska Route 1) is a highway in the U.S. state of Alaska, extending from Anchorage near Merrill Field to Glennallen on the Richardson Highway. The Tok Cut-Off is often considered part of the Glenn Highway, for a total length of . Route description The longest stretch of freeway in Alaska runs mostly along the Glenn Highway, beginning in north Anchorage, continuing onto the Parks Highway at the interchange of the two roads, and ending in the city limits of Wasilla, for a total of approximately 38 miles (61 km). This portion of the Glenn Highway is the only road access to Anchorage for most of the state (with the exception of the Kenai Peninsula on the Seward Highway), and as such is the main traffic corridor for Anchorage's suburbs in the Chugiak-Eagle River and Mat-Su areas. The highest point on the highway is at ''Eureka Summit'', which sits on the divide between the Chugach and Talkeetna mountain ranges. History The highway orig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kenai Peninsula
The Kenai Peninsula ( Dena'ina: ''Yaghenen'') is a large peninsula jutting from the coast of Southcentral Alaska. The name Kenai (, ) is derived from the word "Kenaitze" or "Kenaitze Indian Tribe", the name of the Native Athabascan Alaskan tribe, the Kahtnuht’ana Dena’ina ("People along the Kahtnu (Kenai River)"), who historically inhabited the area. They called the Kenai Peninsula ''Yaghanen'' ("the good land"). Geography The peninsula extends about southwest from the Chugach Mountains, south of Anchorage. It is separated from the mainland on the west by Cook Inlet and on the east by Prince William Sound. Most of the peninsula is part of the Kenai Peninsula Borough. Athabaskan and Alutiiq Native groups lived on the peninsula for thousands of years prior to colonization during the Russian America era. The glacier-covered Kenai Mountains run along the southeast spine of the peninsula along the coast of the Gulf of Alaska. Much of the range is within Kenai Fjords Natio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Magnitude Of 2018 Anchorage Earthquake
Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of magnitude, the class of scale having a fixed value ratio to the preceding class *Scalar (mathematics), a quantity defined only by its magnitude Astronomy * Absolute magnitude, the brightness of a celestial object corrected to a standard luminosity distance *Apparent magnitude, the calibrated apparent brightness of a celestial object *Instrumental magnitude, the uncalibrated apparent magnitude of a celestial object *Limiting magnitude, the faintest apparent magnitude of a celestial body that is detectable or detected by a given instrument. *Magnitude (astronomy), a measure of brightness and brightness differences used in astronomy *Magnitude of eclipse or geometric magnitude, the size of the eclipsed part of the Sun during a solar eclipse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fault (geology)
In geology, a fault is a Fracture (geology), planar fracture or discontinuity in a volume of Rock (geology), rock across which there has been significant displacement as a result of rock-mass movements. Large faults within Earth's crust (geology), crust result from the action of Plate tectonics, plate tectonic forces, with the largest forming the boundaries between the plates, such as the megathrust faults of subduction, subduction zones or transform faults. Energy release associated with rapid movement on active faults is the cause of most earthquakes. Faults may also displace slowly, by aseismic creep. A ''fault plane'' is the Plane (geometry), plane that represents the fracture surface of a fault. A ''fault trace'' or ''fault line'' is a place where the fault can be seen or mapped on the surface. A fault trace is also the line commonly plotted on geological maps to represent a fault. A ''fault zone'' is a cluster of parallel faults. However, the term is also used for the zone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Mechanism
The focal mechanism of an earthquake describes the Fault (geology)#Slip.2C heave.2C throw, deformation in the Hypocenter, source region that generates the seismic waves. In the case of a Fault (geology), fault-related event, it refers to the orientation of the fault plane that slipped, and the slip Euclidean vector, vector and is also known as a fault-plane solution. Focal mechanisms are derived from a solution of the moment tensor for the earthquake, which itself is estimated by an analysis of observed seismic waveforms. The focal mechanism can be derived from observing the pattern of "first motions", whether the first arriving P waves break up or down. This method was used before waveforms were recorded and analysed digitally, and this method is still used for earthquakes too small for easy moment tensor solution. Focal mechanisms are now mainly derived using semi-automatic analysis of the recorded waveforms. Moment tensor solutions The moment tensor solution is displayed gra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Moment Magnitude Scale
The moment magnitude scale (MMS; denoted explicitly with or Mwg, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. was defined in a 1979 paper by Thomas C. Hanks and Hiroo Kanamori. Similar to the local magnitude scale, local magnitude/Richter scale () defined by Charles Francis Richter in 1935, it uses a logarithmic scale; small earthquakes have approximately the same magnitudes on both scales. Despite the difference, news media often use the term "Richter scale" when referring to the moment magnitude scale. Moment magnitude () is considered the authoritative magnitude scale for ranking earthquakes by size. It is more directly related to the energy of an earthquake than other scales, and does not saturatethat is, it does not underestimate magnitudes as other scales do in certain conditions. It has become the standard scale used by seismological authorities like the United State ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Washington (state)
Washington, officially the State of Washington, is a U.S. state, state in the Pacific Northwest region of the United States. It is often referred to as Washington State to distinguish it from Washington, D.C., the national capital, both named after George Washington (the first President of the United States, U.S. president). Washington borders the Pacific Ocean to the west, Oregon to the south, Idaho to the east, and shares Canada–United States border, an international border with the Provinces and territories of Canada, Canadian province of British Columbia to the north. Olympia, Washington, Olympia is the List of capitals in the United States, state capital, and the most populous city is Seattle. Washington is the List of U.S. states and territories by area, 18th-largest state, with an area of , and the List of U.S. states and territories by population, 13th-most populous state, with a population of just less than 8 million. The majority of Washington's residents live ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tacoma, Washington
Tacoma ( ) is the county seat of Pierce County, Washington, United States. A port city, it is situated along Washington's Puget Sound, southwest of Seattle, southwest of Bellevue, Washington, Bellevue, northeast of the state capital, Olympia, Washington, Olympia, northwest of Mount Rainier National Park, and east of Olympic National Park. The city's population was 219,346 at the time of the 2020 United States census, 2020 census. Tacoma is the second-largest city in the Puget Sound area and the List of municipalities in Washington, third-most populous in the state. Tacoma also serves as the center of business activity for the South Puget Sound, South Sound region, which has a population of about 1 million. Tacoma adopted its name after the nearby Mount Rainier, called in the Lushootseed, Puget Sound Salish dialect, and “Takhoma” in an anglicized version. It is locally known as the "City of Destiny" because the area was chosen to be the western terminus of the Northern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1964 Alaska Earthquake
The 1964 Alaska earthquake, also known as the Great Alaska earthquake and Good Friday earthquake, occurred at 5:36 PM Alaska Standard Time, AKST on Good Friday, March 27, 1964.M 9.2 - The 1964 Prince William Sound, Alaska Earthquake: Overview USGS Earthquake Hazards Program. Across south-central Alaska, ground fissures, collapsing structures, and tsunamis resulting from the earthquake caused about 139 deaths. Lasting four minutes and thirty-eight seconds, the magnitude 9.2–9.3 megathrust earthquake remains the most powerful earthquake ever recorded in North America, and the Largest earthquakes by magnitude#Largest earthquakes by magnitude, second most powerful earthquake ever recorded i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megathrust Earthquake
Megathrust earthquakes occur at convergent plate boundaries, where one tectonic plate is forced underneath another. The earthquakes are caused by slip along the thrust fault that forms the contact between the two plates. These interplate earthquakes are the planet's most powerful, with moment magnitudes (''Mw'') that can exceed 9.0. Since 1900, all earthquakes of magnitude 9.0 or greater have been megathrust earthquakes. The thrust faults responsible for megathrust earthquakes often lie at the bottom of oceanic trenches; in such cases, the earthquakes can abruptly displace the sea floor over a large area. As a result, megathrust earthquakes often generate tsunamis that are considerably more destructive than the earthquakes themselves. Teletsunamis can cross ocean basins to devastate areas far from the original earthquake. Terminology and mechanism The term ''megathrust'' refers to an extremely large thrust fault, typically formed at the plate interface along a subduction zo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
