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 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 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. The earthquake seemed too small to spawn the huge local wave and scientists struggled for decades to figure out what happened. 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. The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands on April 1, 1946, and generated a Pacific-wide tsunami. Near-field surveyofthe 1946 Aleutian tsunami on Unimak and Sanak Islands Emile A. Okal1,George Plafker2,Costas E. Synolakis3, and Jose´ C. Borrero3 1 Department … Description. 2. 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. 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 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 got more and more puzzling as a seafloor search failed to reveal what scientists expected to find. 2. Despite the destruction to the Aleutian Island Unimak, the tsunami had … This earthquake is notable because it generated a disproportionately large tsunami given its surface wave magnitude (tsunami magnitude, M t , 9.3 [ Abe , 1979 ]). But the lighthouse tenders would never return to their homes in the Lower 48. World War II was over. World War II was over. It completely destroyed the U.S. Coast Guard’s Scotch Cap lighthouse on Unimak and killed all five of its occupants. The tsunami arrived at … The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1. Just 21 minutes ago, a 5.0-magnitude earthquake struck near the town of Akutan, Alaska. 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. World War II was over. The lighthouse was a few miles from the epicenter on Unimak Island, 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 quake triggered devastating tidal waves throughout the Pacific, particularly in Hawaii. The April 1, 1946 Pacific-wide tsunami was caused by a magnitude 7.3 Ms earthquake that occurred south of Unimak Island, Alaska. 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. On April 1, 1946, at 12:29 GMT, an earthquake occurred in the Aleutian Islands of Alaska. 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. Witnesses told of waves inundating streets, homes, and storefronts. They had survived. 1946 Aleoeten aardbeving - 1946 Aleutian Islands earthquake. 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. Before the tsunami dissipated it took the lives of more than 165 people and cause over $26 million (1946 dollars) in damage. M 8.6 - 1946 Aleutian Islands (Unimak Island) Earthquake, Alaska Total damage was estimated at $26 million and, two years later, the United States established a Pacific Tsunami Warning Center in Hawaii. The effects of the tsunami were felt along the west coast of the United States, in Washington, Oregon, and California.
The earthquake seemed too small to spawn the huge local wave and scientists struggled for decades to figure out what happened. The 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1. They never knew what hit them in the 2 … The seafloor along the fault was elevated, triggering a Pacific-wide tsunami with multiple destructive waves at heights ranging from 45–130 ft. 39811 km 2 (=15371 sqare miles) as a first-order estimate. The 1946 M S 7.4 earthquake may have ruptured a section of the megathrust offshore Unimak Island. This tsunami carried a wave height exceeding one hundred feet. In spring of 1946, five men stationed at the Scotch Cap lighthouse had reasons to be happy. On Unimak Island's Pacific shore, a runup of 42 m destroyed the lighthouse at Scotch Cap. Its tsunami magnitude, 9.3, is comparable to the 9.1 magnitude of the 2011 Tohoku tsunami. 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. Many victims were swept out to sea by receding water. 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 … The tsunami obliterated the Scotch Cap Lighthouse on Unimak Island, Alaska among others, and killed all five lighthouse keepers. (U.S. Coast Guard photographs) Tsunami waves advancing across Coconut Island, at the Hilo Bay waterfront. The tsunami obliterated the Scotch Cap Lighthouse on Unimak Island, Alaska among others, and killed all five lighthouse keepers… Scotch Cap Lighthouse on Unimak Island, Alaska, before and after the April 1, 1946 earthquake and tsunami. This tsunami carried a wave height exceeding one hundred feet. 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. 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. 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. A long-simmering scientific debate continues over just what caused the 1946 tsunami. The tsunami severely damaged Pacific islands and coastal areas from Alaska to Antarctica. 1946 headline display newspaper ALASKA ALEUTIAN ISLANDS EARTHQUAKE & resulting Hawaii Tsunami strikes HILO - inv # 4B-227. During the quake, a large section of seafloor was uplifted along the fault where the quake occurred, producing a large, Pacific-wide tsunami. 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).

Many victims were swept out to sea by receding water. 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 magnitude 8.1 earthquake caused 165 casualties. The Earthquake Event Page application supports most recent browsers, view supported browsers. 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 1946 Aleutian Islands earthquake occurred near the Aleutian Islands, Alaska on April 1. The lighthouse was a steel-reinforced concrete structure standing about ninety-five feet above sea level. The wave reached Kauai, Hawaii 4.5 hours after the quake, and Hilo, Hawaii 4.9 hours later. Scotch Cap Lighthouse sits on the southwest shore of Unimak Island two months before the giant wave of April 1, 1946. In California, Fort Bragg reported five- to nine-foot waves. 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. 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. 14) Magnitude: 8.5 – Banda Sea (1938-02-01) 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. Total property damage in Alaska was $250,000 while California experienced one death and $10,000 damage from the tsunami. Despite the destruction to the Aleutian Island Unimak, the tsunami had almost an imperceptible effect on the Alaskan mainland. Description. Scotch Cap Lighthouse on Unimak Island, Alaska, before and after the April 1, 1946 earthquake and tsunami. 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. 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 spring of 1946, five men stationed at the Scotch Cap lighthouse had reasons to be happy. 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. Their lonely Coast Guard assignment on Unimak Island would be over in a few months. 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. On Unimak Island's Pacific shore, a runup of 42 m destroyed the lighthouse at Scotch Cap. The tsunami caused much damage in Maui as well. Total property damage in Alaska was $250,000 while California experienced one death and $10,000 damage from the tsunami. On April 1, 1946, the sea floor ruptured just south of Unimak Island in the Aleutian Islands. [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. 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