Description. The magnitude 8.1 earthquake caused 165 casualties. The M w 8.6 earthquake in 1946 off the Pacific shore of Unimak Island at the end of the Alaska Peninsula generated a far‐field tsunami that crossed the Pacific to Antarctica. Hawaii experienced the worst damage, with 159 deaths (96 at Hilo) and $26 million in property loss. (Courtesy U.S. Coast Guard) Scotch Cap lighthouse two months before the tsunami of April 1, 1946. This earthquake is notable because it generated a disproportionately large tsunami given its surface wave magnitude (tsunami magnitude, M t, 9.3 [Abe, 1979]). On April 1, 1946, the sea floor ruptured just south of Unimak Island in the Aleutian Islands. 1946-04-01 12:29:01 UTC 8.6 magnitude, 15 km depth Akutan, Alaska, United States 8.6 magnitude earthquake 1946-04-01 12:29:01 UTC at 12:29 April 01, 1946 UTC Total damage was estimated at $26 million and, two years later, the United States established a Pacific Tsunami Warning Center in Hawaii. They never knew what hit them in the 2 … Unimak Island, Alaska has had: (M1.5 or greater) 0 earthquakes in the past 24 hours 1 earthquake in the past 7 days; 4 earthquakes in the past 30 days the western Unimak area did not rupture during the 1957 earthquake. M 8.6 - 1946 Aleutian Islands (Unimak Island) Earthquake, Alaska 39811 km 2 (=15371 sqare miles) as a first-order estimate. The wave reached Kauai, Hawaii 4.5 hours after the quake, and Hilo, Hawaii 4.9 hours later. Their lonely Coast Guard assignment on Unimak Island would be over in a few months. Generation by one or more major earthquake triggered submarine landslides near the shelf edge south of Unimak Island seems to be the only viable mechanism to account for the data on wave arrival time, run-up heights, and the distribution of tsunamis across the Pacific. On April 1, 1946 at 4:28 am (12:28 UTC), an 8.6 moment magnitude earthquake struck off the coast of Unimak Island in Alaska’s Aleutian Islands, generating a tsunami that caused the greatest damage and number of deaths in Hawaii’s history, leading to the creation of the United States’ first tsunami warning system. 1946 Aleutian Islands Earthquake (Unimak Island) in Alaska. The tsunami magnitude of 9.3 is comparable to the magnitude 9.1 tsunami that devastated the Tohoku coast of Japan in 2011. The largest of these was a M8.6 earthquake on April 1, 1946, which generated a large tsunami that caused destruction and loss of life both locally on Unimak Island and more distantly at Hilo, Hawaii. The earthquake seemed too small to spawn the huge local wave and scientists struggled for decades to figure out what happened. The tsunami obliterated the Scotch Cap Lighthouse on Unimak Island, Alaska among others, and killed all five lighthouse keepers. The Mw 8.6 earthquake in 1946 off the Pacific shore of Unimak Island at the end of the Alaska Peninsula generated a far-field tsunami that crossed the Pacific to Antarctica. It was followed by a Pacific-wide tsunami.The earthquake was a magnitude 8.6 (originally rated 7.8 but later revised), with its epicenter at 52.8°N, 163.5°W, and focal depth of 25 km. In 1946, the M8.6 earthquake on Unimak Island in Alaska occurred on April 1 and triggered a gigantic 55 feet high tsunami, travelling at 500 miles an hour across the Pacific Ocean. The magnitude 8.1 earthquake caused 165 casualties. One wave as high as a 13-story building hit locally. Despite the destruction to the Aleutian Island Unimak, the tsunami had … One of the structures affected by the tsunami was the newly built Scotch Cap Lighthouse on Unimak Island, Alaska. De 1946 Aleoeten aardbeving plaatsvond nabij de Aleoeten, Alaska april 1. One wave as high as a 13-story building hit locally. [3], The tsunami was unusually powerful for the size of the earthquake. The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1. In spring of 1946, five men stationed at the Scotch Cap lighthouse had reasons to be happy. On April Fools Day in 1946 an earthquake off the coast of the Aleutian Islands in Alaska spawned a series of waves known as a tsunami. The 1946 M S 7.4 earthquake may have ruptured a section of the megathrust offshore Unimak Island. Van Wikipedia, ... met meerdere verwoestende golven op een hoogte variërend 45-130 ft. De tsunami uitgewist de Scotch Cap Lighthouse op Unimak Island, Alaska onder anderen, en doodde alle vijf vuurtorenbewaarders. [6], Earthquake near the Aleutian Islands, Alaska, "Comments for the Significant Earthquake", https://www.civilbeat.org/2011/03/9558-a-history-of-tsunamis-in-hawaii/, Tsunami Animation: Unimak Island, Aleutian Islands, 1946, Alaska National Interest Lands Conservation Act, https://en.wikipedia.org/w/index.php?title=1946_Aleutian_Islands_earthquake&oldid=949891129, Short description is different from Wikidata, Creative Commons Attribution-ShareAlike License, This page was last edited on 9 April 2020, at 03:21. World War II was over. The 1946 M S 7.4 earthquake may have ruptured a section of the megathrust offshore Unimak Island. On the first of April 1946 Alaska experienced one of its greatest tsunamis, triggered by an earthquake of magnitude 8.1 near Unimak Island in the Aleutian Island Chain. Researchers did see colorful corals and an unusual methane seep teaming with marine life, but the sea floor looked as if it had been undisturbed for millennia. The shock had a moment magnitude of 8.6 and a maximum Mercalli intensity of VI (Strong). Before the tsunami dissipated it took the lives of more than 165 people and cause over $26 million (1946 dollars) in damage. Another six were killed in other parts of Hawaii. Your email address will not be published. A long-simmering scientific debate continues over just what caused the 1946 tsunami. [3], Waves reportedly traveled across the ocean at 500 miles an hour and measured 55 feet high, crest to trough, according to the USGS. In 1946 at Unimak Pass, Alaska, a tsunami destroyed the lighthouse at Scotch Cap, Unimak Island, took 159 lives on the Hawaiian Islands, damaged island coastal facilities across the south Pacific, and destroyed a hut in Antarctica. The shock had a moment magnitude of 8.6 and a maximum Mercalli intensity of VI (Strong). We focus on the deformation of Westdahl and Fisher volcanoes and the plate coupling in the source region of the 1946 earthquake. The Mw 8.6 earthquake in 1946 off the Pacific shore of Unimak Island at the end of the Alaska Peninsula generated a far-field tsunami that crossed the Pacific to Antarctica. On the first of April 1946 Alaska experienced one of its greatest tsunamis, triggered by an earthquake of magnitude 8.1 near Unimak Island in the Aleutian Island Chain. The Mw 8.6 earthquake in 1946 off the Pacific shore of Unimak Island at the end of the Alaska Peninsula generated a far-field tsunami that crossed the Pacific to Antarctica. 14) Magnitude: 8.5 – Banda Sea (1938-02-01) Its tsunami magnitude, 9.3, is comparable to the 9.1 magnitude of the 2011 Tohoku tsunami.

The quake triggered devastating tidal waves throughout the Pacific, particularly in Hawaii. Their lonely Coast Guard assignment on Unimak Island … The event triggered a Pacific-wide tsunami with multiple destructive waves at heights ranging from 45–130 ft. World War II was over. They had survived. But the lighthouse tenders would never return to their homes in the Lower 48. This earthquake is notable because it generated a disproportionately large tsunami given its surface wave magnitude (tsunami magnitude, M t , 9.3 [ Abe , 1979 ]). This tsunami carried a wave height exceeding one hundred feet. The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1. (U.S. Coast Guard photographs) Tsunami waves advancing across Coconut Island, at the Hilo Bay waterfront. They had survived. [5] The large-scale destruction prompted the creation of the Seismic Sea Wave Warning System, which became the Pacific Tsunami Warning Center in 1949. On April 1, 1946 at 4:28 am (12:28 UTC), an 8.6 moment magnitude earthquake struck off the coast of Unimak Island in Alaska’s Aleutian Islands, generating a tsunami that caused the greatest damage and number of deaths in Hawaii’s history, leading to the creation of the United States’ first tsunami warning system. The tsunami was also noticed in Santa Barbara and the greater Los Angeles area. A tsunami over 100 ft high, triggered by an earthquake south of Unimak Island, struck the Scotch Cap Lighthouse at 2:18 a.m on April 1, 1946. April 1, 1946, was witness to a deadly tsunami earthquake generated south of Unimak Island with a moment magnitude of 8.6. that caused consequential events that lent to a … April 1946 Unimak Island, USA Images On April 1, 1946, at 12:29 [local time] a rather strong magnitude 8.6 earthquake occurred with source to the south of Unimak Island, causing one of the most destructive tsunamis in the Pacific Ocean. Wave heights reached an estimated 115 feet in Alaska, and averaged 30 feet in Hawaii, where the tsunami struck without warning nearly 5 hours after the earthquake. The lighthouse was a steel-reinforced concrete structure standing about ninety-five feet above sea level. Total property damage in Alaska was $250,000 while California experienced one death and $10,000 damage from the tsunami. On April 1, 1946, an undersea earthquake off the Alaskan coast triggers a massive tsunami that kills 159 people in Hawaii. 316 km 2 (=122 sqare miles) as a first-order estimate. This tsunami carried a wave height exceeding one hundred feet. Total property damage in Alaska was $250,000 while California experienced one death and $10,000 damage from the tsunami. At the lighthouse 5 men lost … On Unimak Island's Pacific shore, a runup of 42 m destroyed the lighthouse at Scotch Cap. Hilo’s waterfront on the island of Hawaii was completely obliterated and 159 people lost the lives there. The tremor was recorded early morning on Wednesday 4 November 2020 at 3.23 am local time, at a moderately shallow depth of 27 miles below the surface. Seawater displaced by the giant earthquake sent a 100-foot wave into the Scotch Cape lighthouse on Unimak, destroying the concrete structure and killing the five men inside. AEC located nearly 100 aftershocks (open circles) through the end of the month (M>=1.9). (ITIC Archives; Photograph by Ted Lusdy). (U.S. Coast Guard photographs) Tsunami waves advancing across Coconut Island, at the Hilo Bay waterfront. In spring of 1946, five men stationed at the Scotch Cap lighthouse had reasons to be happy. Seawater displaced by the giant earthquake sent a 100-foot wave into the Scotch Cape lighthouse on Unimak, destroying the concrete structure and killing the five men inside. 1946-11-01 11:14:28 UTC 7.0 magnitude, 25 km depth Andreanof Islands, Aleutian Island 7.0 magnitude earthquake 1946-11-01 11:14:28 UTC at 11:14 November 01, 1946 UTC In 1946, megathrust seismicity along the Unimak segment of the Alaska subduction zone generated the largest ever recorded Alaska/Aleutian tsunami. (ITIC Archives; Photograph by Ted Lusdy). Wave heights reached an estimated 115 feet in Alaska, and averaged 30 feet in Hawaii, where the tsunami struck without warning nearly 5 hours after the earthquake. As with the earlier event it also caused a dangerous tsunami that caused significant damage in the Aleutian Islands and in Hawaii and was observed as far away as Chile. The seafloor along the fault was elevated, triggering a Pacific-wide tsunami with multiple destructive waves at heights ranging from 45–130 ft. It resulted in 165–173 casualties and over $26 million in damage. 1994)--but was to the west of the 1946 earthquake, near the Andreanof Islands.

Many victims were swept out to sea by receding water. The most detailed and documented accounts of the tsunami come from Scotch Cap, located on Unimak Island, and the Hawaiian Islands. The event was classified as a tsunami earthquake due to the discrepancy between the size of the tsunami and the relatively low surface wave magnitude. The largest of these was a M8.6 earthquake on April 1, 1946, which generated a large tsunami that caused destruction and loss of life both locally on Unimak Island and more distantly at Hilo, Hawaii. The event triggered a Pacific-wide tsunami with multiple destructive waves at heights ranging from 45–130 ft. In spring of 1946, five men stationed at the Scotch Cap Lighthouse had reasons to be happy. Unimak Island acquired between 1998 and 2001 and interpret the observed deformation in terms of volcanic and tectonic activities. For this puzzling event, maximum near-field run-up (42 m) is more than 6 times the computed average dip slip on the source fault (Johnson and Satake, 1997). 2. The tsunami magnitude of 9.3 is comparable to the magnitude 9.1 tsunami that devastated the Tohoku coast of Japan in 2011. Natural history. 2. They had survived. The effects of the tsunami also reached Washington, Oregon, and California. The effects of the tsunami were felt along the west coast of the United States, in Washington, Oregon, and California. It completely destroyed the U.S. Coast Guard’s Scotch Cap lighthouse on Unimak and killed all five of its occupants. The Earthquake Event Page application supports most recent browsers, view supported browsers. By John J. Miller, Roland von Huene, and Holly Ryan This earthquake is notable because it generated a disproportion-ately large tsunami given its surface wave magnitude (tsu-nami magnitude, M t, 9.3 [Abe, 1979]). The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1. On April Fools Day in 1946 an earthquake off the coast of the Aleutian Islands in Alaska spawned a series of waves known as a tsunami. 13) Magnitude: 8.6 – South of Alaska Unimak Island Earthquake, Alaska (1946-04-01) This earthquake struck near Aleutian Islands and claimed between 165 – 173 casualties and resulted in nearly $26 million dollars of destruction. The M w 8.6 earthquake in 1946 off the Pacific shore of Unimak Island at the end of the Alaska Peninsula generated a far-field tsunami that crossed the Pacific to Antarctica. On April 1, 1946, at 12:29 GMT, an earthquake occurred in the Aleutian Islands of Alaska. On April 1, 1946, the sea floor ruptured just south of Unimak Island in the Aleutian Islands. De schok had een ogenblik magnitude van 8,6 en een maximale Mercalli intensiteit van VI ( Strong).Het resulteerde in 165-173 slachtoffers en meer dan $ 26 miljoen in schade. The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands on April 1, 1946, and generated a Pacific-wide tsunami. The shock had a moment magnitude of 8.1 and a maximum Mercalli intensity of VI (Strong).It resulted in 165 casualties (159 people on Hawaii and six in Alaska) and over $26 million in damage.
The earthquake seemed too small to spawn the huge local wave and scientists struggled for decades to figure out what happened. Another six were killed in other parts of Hawaii. The deadliest earthquake in the US is the 1906 San Francisco earthquake. The lighthouse was completely destroyed and the entire five-man crew was killed. In 1946 at Unimak Pass, Alaska, a tsunami destroyed the lighthouse at Scotch Cap, Unimak Island, took 159 lives on the Hawaiian Islands, damaged island coastal facilities across the south Pacific, and destroyed a hut in Antarctica. (adsbygoogle = window.adsbygoogle || []).push({}); Your email address will not be published. Aftershocks of the 6.5 quake: Unimak Island Region, Alaska (USA), 30 Oct 1946 07h47 Show info about this Based on its magnitude, the fault that was active during the quake ruptured along a surface of approx. When the Alaska National Interest Lands Conservation Act was passed on 2 December 1980, 910,000 acres (370,000 ha) of the island was designated as wilderness. Its tsunami magnitude, 9.3, is comparable to the 9.1 magnitude of the 2011 Tohoku tsunami. The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1. When the Alaska National Interest Lands Conservation Act was passed on 2 December 1980, 910,000 acres (370,000 ha) of the island was designated as wilderness. The April 1, 1946 Pacific-wide tsunami was caused by a magnitude 7.3 Ms earthquake that occurred south of Unimak Island, Alaska. The 1946 Unimak Tsunami Earthquake Area: Revised Tectonic Structure in Reprocessed Seismic Images and a Suspect Near-Field Tsunami Source . Hawaii experienced the worst damage, with 159 deaths (96 at Hilo) and $26 million in property loss. Unimak Island is part of the Alaskan continent that is geographically part of the Alaska Scotch Cap Lighthouse sits on the southwest shore of Unimak Island two months before the giant wave of April 1, 1946. 1946 Aleoeten aardbeving - 1946 Aleutian Islands earthquake. Their lonely Coast Guard assignment on Unimak Island would be over in a few months. It completely destroyed the U.S. Coast Guard’s Scotch Cap lighthouse on Unimak and killed all five of its occupants. 1 The earthquake was ~7.3 magnitude. [4] The residents of these islands were caught off-guard by the onset of the tsunami due to the inability to transmit warnings from the destroyed posts at Scotch Cap, and the tsunami is known as the April Fools' Day Tsunami in Hawaii because it happened on April 1 and many thought it to be an April Fool's Day prank. This earthquake has The tsunami reached the Hawaiian Islands five hours later, causing considerable damage and loss of life. The tsunami severely damaged Pacific islands and coastal areas from Alaska to Antarctica. add Nature:Earthquake and tsunami:Unimak Island 1946 to 'my astro' Biography Aleutian earthquake of magnitude 8,6 (updated 2006).A devastating tsunami followed the shock.The height of the tsunami reached 42 m.In Hawaii 159 deaths were to blame as the waves still climbed up to 12 m. A mystery surrounded this earthquake for a time. Oregon reported a ten-foot wave. In the middle of the night, 13,000 The tsunami had little effect on the Alaskan mainland, due to the presence of the Aleutian Islands, which absorbed the brunt of the tsunami’s power. A 7.8 earthquake off the coast of the Aleutian Islands of Alaska on April 1, 1946 triggered a tsunami which caused the death of 165 people and caused more than $26 million in damage. In spring of 1946, five men stationed at the Scotch Cap lighthouse had reasons to be happy. Despite the destruction to the Aleutian Island Unimak, the tsunami had almost an imperceptible effect on the Alaskan mainland. Their lonely Coast Guard assignment on Unimak Island would be over in a few months. It resulted in 165–173 casualties and over $26 million in damage. World War II was over. It is the charter member of "tsunami" earthquakes that produce outsized far-field tsunamis for the recorded magnitude. The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1. Aftershocks of the 8.6 quake 1946 Aleutian Islands (Unimak Island) Earthquake, Alaska (USA, 1946-04-01 12:29 UTC More info Based on its magnitude, the fault that was active during the quake ruptured along a surface of approx. Required fields are marked *. The great Mw=8.7 Rat Islands underthrusting earthquake (larger star on the above map) of February 4, 1965, ruptured a 600-km segment of the western end of the Aleutian Islands (black solid line). On Unimak Island's Pacific shore, a runup of 42 m destroyed the lighthouse at Scotch Cap. Just 21 minutes ago, a 5.0-magnitude earthquake struck near the town of Akutan, Alaska. The tsunami obliterated the Scotch Cap Lighthouse on Unimak Island, Alaska among others, and killed all five lighthouse keepers… Waves there demolished 77 homes and many other buildings. During the quake, a large section of seafloor was uplifted along the fault where the quake occurred, producing a large, Pacific-wide tsunami. The seafloor along the fault was elevated, triggering a Pacific-wide tsunami with multiple destructive waves at heights ranging from 45–130 ft. The tsunami caused much damage in Maui as well. The tsunami arrived at … add Nature:Earthquake and tsunami:Unimak Island 1946 to 'my astro' Biography Aleutian earthquake of magnitude 8,6 (updated 2006).A devastating tsunami followed the shock.The height of the tsunami reached 42 m.In Hawaii 159 deaths were to blame as the waves still climbed up to 12 m. The low coupling across the rupture zone of the 1946 earthquake is a strong argument for the idea that the earthquake and tsunami did not result from a purely double-couple (earthquake) source. They had survived. The 1946 M S 7.4 earthquake may have ruptured a section of the megathrust offshore Unimak Island. The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands on April 1, 1946, and generated a Pacific-wide tsunami. The 1946 Unimak earthquake occurred along the plate margin off Unimak Island in an unusually structured region that transitions from the Alaska to the Aleutian convergent margin system. 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