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1946 Aleutian Islands Earthquake
The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1, 1946. The shock measured () 8.6, 9.3 or () 7.4. It had a maximum Mercalli intensity of VI (''Strong''). It resulted in 165–173 casualties and over US$26 million () in damage. The seafloor along the fault was elevated, triggering a Pacific-wide tsunami with multiple destructive waves at heights ranging from . The tsunami obliterated the Scotch Cap Lighthouse on Unimak Island, Alaska among others, and killed all five lighthouse keepers. Despite the destruction to the Aleutian Island Unimak, the tsunami had almost an imperceptible effect on the Alaskan mainland. Tectonic setting The Aleutian Islands are a group of 14 large and 55 smaller volcanic islands situated between mainland Alaska and Kamchatka. They are situated along the Aleutian Trench as they were formed by the active subduction of the oceanic Pacific plate underneath the continental crust of the North American plate. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hilo, Hawaii
Hilo () is the largest settlement in and the county seat of Hawaii County, Hawaiʻi, United States, which encompasses the Island of Hawaiʻi, and is a census-designated place (CDP). The population was 44,186 according to the 2020 census. It is the fourth-largest settlement in the state of Hawaiʻi, the largest settlement in the state outside of Oahu, and the largest settlement in the state outside of the Greater Honolulu Area. Hilo is in the District of South Hilo. The city overlooks Hilo Bay and has views of two shield volcanoes, Mauna Loa, an active volcano, and Mauna Kea, a dormant volcano. The Hilo bayfront has been destroyed by tsunamis twice. The majority of human settlement in Hilo stretches from Hilo Bay to Waiākea-Uka, on the flanks of the volcanoes. Hilo is home to the University of Hawaii at Hilo, ʻImiloa Astronomy Center, as well as the Merrie Monarch Festival, a week-long celebration, including three nights of competition, of ancient and modern hula th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2017 Komandorski Islands Earthquake
On July 18, 2017, an earthquake struck near the Komandorski Islands, east of the Kamchatka Peninsula in the Bering Sea at 11:34 local time (23:34 UTC on July 17). Although there were no casualties from this earthquake, it was notable for a rare characteristic known as supershear, and is one of the few times a large supershear earthquake has been observed. It was preceded by a few foreshocks months earlier, and aftershocks that continued for nearly six months. Tectonic setting The 7.8 earthquake nucleated along the Bering fracture zone, parallel to the Aleutian Islands arc and Aleutian Subduction Zone. This is a transform fault between the Pacific and North American plates, and in between, the Komandorski Sliver. Formed from the highly oblique movement of the Pacific plate, the direction of convergence is nearly parallel to the trench at 7.8 mm/yr. The Bearing Fracture Zone acts as a back-arc fault to accommodate the lateral motion at a rate of 5.1 mm/yr. The sa ... [...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] |
Maui
Maui (; Hawaiian language, Hawaiian: ) is the second largest island in the Hawaiian archipelago, at 727.2 square miles (1,883 km2). It is the List of islands of the United States by area, 17th-largest in the United States. Maui is one of Maui County, Hawaii, Maui County's five islands, along with Molokai, Molokai, Lanai, Lānai, Kahoʻolawe, Kahoolawe, and Molokini. In 2020, Maui had a population of 168,307, the third-highest of the Hawaiian Islands, behind Oahu, Oahu and Hawaii (island), Hawaii Island. Kahului, Hawaii, Kahului is the largest census-designated place (CDP) on the island, with a 2020 population of 28,219. It is Maui's commercial and financial hub. Wailuku, Hawaii, Wailuku is the county seat and was the third-largest CDP . Other significant populated areas include Kihei, Hawaii, Kīhei (including Wailea, Hawaii, Wailea and Makena, Hawaii, Makena in the Kihei Town CDP), Lahaina, Hawaii, Lāhainā (including Kaanapali, Kāanapali and Kapalua in the Lāhainā T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kauai
Kauai (), anglicized as Kauai ( or ), is one of the main Hawaiian Islands. It has an area of 562.3 square miles (1,456.4 km2), making it the fourth-largest of the islands and the 21st-largest island in the United States. Kauai lies 73 miles (117 km) northwest of Oahu, across the Kauai Channel. The island's 2020 population was 73,298. Styling itself the "Garden Isle", Kauai is the site of Waimea Canyon State Park and Nā Pali Coast State Park. It forms the bulk of Kauai County, which includes Niihau as well as the small nearby islands of Kaula and Lehua. Etymology and language Hawaiian narrative derives the name's origin from the legend of Hawaiiloa, the Polynesian navigator credited with discovering the Hawaiian Islands. The story relates that he named the island after a favorite son; a possible translation of Kauai is "place around the neck", describing how a father would carry his child. Another possible translation is "food season". Kauai was known for its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
P Wave
A P wave (primary wave or pressure wave) is one of the two main types of elastic body waves, called seismic waves in seismology. P waves travel faster than other seismic waves and hence are the first signal from an earthquake to arrive at any affected location or at a seismograph. P waves may be transmitted through gases, liquids, or solids. Nomenclature The name ''P wave'' can stand for either pressure wave (as it is formed from alternating compressions and rarefactions) or primary wave (as it has high velocity and is therefore the first wave to be recorded by a seismograph). The name '' S wave'' represents another seismic wave propagation mode, standing for secondary or shear wave, a usually more destructive wave than the primary wave. Seismic waves in the Earth Primary and secondary waves are body waves that travel within the Earth. The motion and behavior of both P and S waves in the Earth are monitored to probe the interior structure of the Earth. Discontinuities i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
S Wave
__NOTOC__ In seismology and other areas involving elastic waves, S waves, secondary waves, or shear waves (sometimes called elastic S waves) are a type of elastic wave and are one of the two main types of elastic body waves, so named because they move through the body of an object, unlike surface waves. S waves are transverse waves, meaning that the direction of particle movement of an S wave is perpendicular to the direction of wave propagation, and the main restoring force comes from shear stress. Therefore, S waves cannot propagate in liquids with zero (or very low) viscosity; however, they may propagate in liquids with high viscosity. Similarly, S waves cannot travel through gases. The name ''secondary wave'' comes from the fact that they are the second type of wave to be detected by an earthquake seismograph, after the compressional primary wave, or P wave, because S waves travel more slowly in solids. Unlike P waves, S waves cannot travel through the molten outer core ... [...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] |
Honolulu
Honolulu ( ; ) is the List of capitals in the United States, capital and most populous city of the U.S. state of Hawaii, located in the Pacific Ocean. It is the county seat of the Consolidated city-county, consolidated City and County of Honolulu County, Hawaii, Honolulu, situated along the southeast coast of the island of Oahu, Oʻahu, and is the westernmost and southernmost major U.S. city as well as westernmost and southernmost U.S. state capital. It is also a major hub for business, finance, hospitality, and military defense in both the state and Oceania. The city is characterized by a mix of various Asian culture, Asian, Western culture, Western, and Oceanian culture, Pacific cultures, reflected in its diverse demography, cuisine, and traditions. is Hawaiian language, Hawaiian for "sheltered harbor" or "calm port"; its old name, , roughly encompasses the area from Nuʻuanu Avenue to Alakea Street and from Hotel Street to Queen Street, which is the heart of the present dow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tsunami Earthquake
In seismology, a tsunami earthquake is an earthquake which triggers a tsunami of significantly greater Seismic magnitude scales, magnitude, as measured by shorter-period seismic waves. The term was introduced by Japanese seismologist Hiroo Kanamori in 1972. Such events are a result of relatively slow Earthquake#Rupture dynamics, rupture velocities. They are particularly dangerous as a large tsunami may arrive at a coastline with little or no warning. Characteristics The distinguishing feature for a tsunami earthquake is that the release of seismic energy occurs at long periods (low frequencies) relative to typical tsunamigenic earthquakes. Earthquakes of this type do not generally show the peaks of seismic wave activity associated with ordinary events. A tsunami earthquake can be defined as an undersea earthquake for which the surface-wave magnitude Ms differs markedly from the moment magnitude scale, moment magnitude Mw, because the former is calculated from surface waves with a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1585 Aleutian Islands Earthquake
The 1585 Aleutian Islands earthquake is the presumed source of a tsunami along the Sanriku coast of Japan on 11 June 1585, known only from vague historical accounts and oral traditions. The event was initially misdated to 1586, which led to it being associated with the deadly earthquakes in Peru and Japan of that year. A megathrust earthquake on the Aleutian subduction zone in the North Pacific Ocean was hypothesized as the tsunami's source. Paleotsunami evidence from shoreline deposits and coral rocks in Hawaii suggest that the 1585 event was a large megathrust earthquake with a moment magnitude () as large as 9.25. Background In 1586, a legend emerged in Japan describing a wave measuring up to two meters which struck near Tokura village in the Motoyoshi District of Miyagi Prefecture. Surviving historical accounts from the period are ambiguous or incomplete, which has made it difficult to identify the tsunami's specific origin. The tsunami was dubbed the "orphan tsunami" or ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Queen Charlotte Fault
The Queen Charlotte Fault is an active transform fault on the boundary between the North American plate and Pacific plates. It is Canada's right-lateral strike-slip equivalent to the San Andreas Fault to the south in California. The Queen Charlotte Fault forms a triple junction at its southern with the Cascadia subduction zone and the Explorer Ridge (the Queen Charlotte triple junction). The Queen Charlotte Fault (QCF) forms a transpressional plate boundary, and is as active as other major transform fault systems (such as San Andreas or Alpine) in terms of slip rates and seismogenic potential. It sustains the highest-known deformation rates among continental or continent-ocean transform systems globally, accommodating more than 50 mm/yr of dextral offset. The entire offshore length has ruptured in seven magnitude 7+ events during the last century, making the cumulative historical seismic moment release higher than any other modern transform plate boundary system. The fau ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
