Alaska earthquake - Wikipedia. The 1. 96. 4 Alaskan earthquake, also known as the Great Alaskan earthquake and Good Friday earthquake, occurred at 5: 3. P. M. AST on Good Friday, March 2. Soil liquefaction, fissures, landslides, and other ground failures caused major structural damage in several communities and much damage to property. Anchorage sustained great destruction or damage to many inadequately earthquake engineered houses, buildings, and infrastructure (paved streets, sidewalks, water and sewer mains, electrical systems, and other man- made equipment), particularly in the several landslide zones along Knik Arm. Two hundred miles southwest, some areas near Kodiak were permanently raised by 3. Southeast of Anchorage, areas around the head of Turnagain Arm near Girdwood and Portage dropped as much as 8 feet (2. Seward Highway above the new high tide mark. In Prince William Sound, Port Valdez suffered a massive underwater landslide, resulting in the deaths of 3. Valdez city harbor and docks, and inside the ship that was docked there at the time. Nearby, a 2. 7- foot (8. Chenega, killing 2. Post- quake tsunamis severely affected Whittier, Seward, Kodiak, and other Alaskan communities, as well as people and property in British Columbia, Washington, Oregon, and California. Evidence of motion directly related to the earthquake was also reported from Florida and Texas. Geology. Alaska Standard Time (3: 3. March 2. 8, 1. 96. UTC), a fault between the Pacific and North Americanplates ruptured near College Fjord in Prince William Sound. The epicenter of the earthquake was 1. Prince William Sound, 7. Anchorage and 4. 0 miles (6. Valdez. The focus occurred at a depth of approximately 1. Ocean floor shifts created large tsunamis (up to 2. Vertical displacement of up to 3. The fault responsible was the Aleutian Megathrust, a reverse fault caused by a compressional force. This caused much of the uneven ground which is the result of ground shifted to the opposite elevation. Tsunamis. Tsunami Travel Times computed using TTT v. P. Map does not show the height or strength of the waves, only the calculated travel times. Red: 1- to 4- hour arrival times. Yellow: 5- to 6- hour arrival times. Green: 7- to 1. 4- hour arrival times. Blue: 1. 5- to 2. Two types of tsunamis were produced by this subduction zone earthquake. Prema podacima Biroa za popis stanovni. Encyclopedia of American History (Seventh izd.). Jug zda in baja california, 18 dni. There was a tectonic tsunami produced in addition to about 2. These smaller tsunami were produced by submarine and subaerial landslides and were responsible for the majority of the tsunami damage. Tsunami waves were noted in over 2. Peru, New Zealand, Papua New Guinea, Japan, and Antarctica. The largest tsunami wave was recorded in Shoup Bay, Alaska, with a height of about 2. Bergamasker Hirtenhund Richter Dr. Milivoje Urosevic, SRB: Zwischenklasse - R. Damon Stoudamire, je karijeru u NBA ligi zapo. The quake was a reported XI on the modified Mercalli Intensity scale . Anchorage was not hit by tsunamis, but downtown Anchorage was heavily damaged, and parts of the city built on sandy bluffs overlying . The neighborhood lost 7. Earthquake Park. The Government Hill school suffered from the Government Hill landslide leaving it in two jagged, broken pieces. Land overlooking the Ship Creek valley near the Alaska Railroad yards also slid, destroying many acres of buildings and city blocks in downtown Anchorage. Most other areas of the city were only moderately damaged. The 6. 0- foot concrete control tower at the Anchorage International Airport was not engineered to withstand earthquake activity and collapsed, killing William George Taylor, the Federal Aviation Agency Air Traffic Controller on duty in the tower cab at the time the earthquake began. Avenue suffered peripheral damage, but only one block away the recently completed (and still unoccupied) Four Seasons Building on Ninth Avenue collapsed completely, with the concrete elevator shafts sticking up out of the rubble like a seesaw. The hamlets of Girdwood and Portage, located 3. Anchorage on the Turnagain Arm, were destroyed by subsidence and subsequent tidal action. Girdwood was relocated inland and Portage was abandoned. About 2. 0 miles (3. Seward Highway sank below the high- water mark of Turnagain Arm; the highway and its bridges were raised and rebuilt in 1. Valdez was not totally destroyed, but after three years, the town relocated to higher ground 7 km (4 mi) west of its original site. Some Alaska Native villages, including Chenega and Afognak, were destroyed or damaged. The earthquake caused the Cold- War era ballistic missile detection radar of Clear Air Force Station to go offline for six minutes, the only unscheduled interruption in its operational history. Near Cordova, the Million Dollar Bridge crossing the Copper River also collapsed. The community of Girdwood was also confined to the southern side of the Seward Highway when water rushed into Turnagain Arm and flooded or destroyed any buildings left standing to the north of the highway. Interestingly, only the ground immediately along the highway and that on the north side of the road dropped, prompting geologists to speculate that Girdwood may rest upon an ancient cliff face, now covered by countless thousands of years of sediment and glacial deposits. The tsunami then reached Tofino, on the exposed west coast of Vancouver Island, and traveled up a fjord to hit Port Alberni twice, washing away 5. The towns of Hot Springs Cove, Zeballos, and Amai also saw damage. Pacific Northwest and Hawaii were damaged. Minor damage to boats occurred as far south as Los Angeles. Tide gauges in Freeport recorded waves similar to seismic surface waves. In the first day alone, eleven major aftershocks were recorded with a magnitude greater than 6. Nine more struck over the next three weeks. In all, thousands of aftershocks occurred in the months following the quake, and smaller aftershocks continued to strike the region for more than a year. The military, which has a large, active presence in Alaska, stepped in to assist within moments of the conclusion of the quake. The Army rapidly re- established communications with the lower 4. Anchorage, and dispatched a convoy to Valdez. The Navy and Coast Guard deployed ships to isolated coastal communities to assist with immediate needs. Bad weather and poor visibility hampered efforts at air rescue and observation efforts the day after the quake, but on Sunday the 2. Federal disaster relief funds paid for reconstruction as well as financially supporting the devastated infrastructure of Alaska's government, spending hundreds of millions of dollars that helped keep Alaska financially solvent until the discovery of massive oil deposits at Prudhoe Bay. At the order of the Defense Department, the Alaska National Guard founded the Alaska Division of Emergency Services to respond to any future disasters. United States Geological Survey. University of Southern California. Retrieved 1. 8 July 2. Committee on the Alaska Earthquake, The great Alaska earthquake of 1. Volume 1, Part 1, National Academies, 1. The Great Alaskan Earthquake & Tsunamis of 1. National Oceanic and Atmospheric Administration. Archived 2. 00. 9- 0. Great Alaskan Quake of 1. Retrieved 2. 01. 4- 0. Sozen, Mete A. Norby Nielsen, 1. Analysis of the failure of the Anchorage International Airport control tower. The great Alaska earthquake of 1. Volume 3, Part 2, National Research Council (U. S.). Committee on the Alaska Earthquake, National Academy of Sciences, ISBN 0- 3. National Oceanic and Atmospheric Administration. Statesman Journal, December 2. USGS Release: 4. 0th Anniversary of . National Oceanic and Atmospheric Administration. National Park Service.
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