Yellowstone National Park had the most energetic swarm of triggered earthquakes. The Great M7.9 Denali Fault, Alaska earthquake of Nov 3, 2002: Geotechnical Engineering Reconnissance Report - A Slide Presentation. On November 3, 2002 a devastating earthquake rattled Alaska. In response to the magnitude 6.7 and 7.9 events, the Alaska Earthquake Information Center (AEIC) staff installed a network of temporary instruments for the aftershock monitoring. This success is a major achievement in U.S. efforts to reduce earthquake losses. Following the Mw 7.9 earthquake on the Denali and Totschunda faults on 3 November 2002, we conducted a reconnaissance of the region to investigate geotechnical and surface rupture features of the event. The Denali fault earthquake sequence be-gan with the moment magnitude (M W) 6.7 Nenana Mountain earthquake on 23 Octo-ber 2002 (Fig. The epicenters (point on the earth surface where the quakes originate) of each of these large earthquakes was about 50 km (30 miles) east of the park, on the Denali fault. Many geologists who study evidence of ancient earthquakes in deposits and landforms along the southernmost San Andreas Fault, where the 1685 earthquake occurred, have concluded that a major quake on this segment of the fault is likely to happen again in the near future. The survival of the Trans-Alaska Oil Pipeline in the 2002 Denali Fault earthquake demonstrates the value of combining careful geologic studies of earthquake hazards and creative engineering in designing and protecting such important structures and lifelines. After the Nenana Mountain earthquake, AEIC installed several temporary seismographs, including some ANSS instruments. A few of these stations are part of the new Advanced National Seismic System (ANSS) being deployed by the USGS and cooperators. At that point, it right-stepped onto the more south-easterly trending Totschunda fault and stopped after rupturing nearly 70 km of it. During the 10 days following the Denali Fault earthquake, geologists from the USGS and Alaska Division of Geological and Geophysical Surveys, as well as several universities, mapped and measured the earthquake rupture on the ground and using aircraft. The runway was rendered unusable by lateral spreading, accompanied by sand boils. The Denali Fault is a Strike-Slip Fault Line Aftershocks of over M 5.0 are being felt near the epicenter of the original quake. It occurred a little before 3:30 p.m. The Denali Fault is a major strike-slip fault in western North America, extending from northwestern British Columbia, Canada, to the central region of the U.S. state of Alaska. Between 1912 and 2002 the level of recorded seismicity on this section of the Denali Fault was very low with the majority of earthquakes M >4.5 occurring on thrust faults to the north or south … Like some other large earthquakes, the Denali Fault quake triggered small shocks as far as 2,000 miles away, mainly in volcanic areas. The temporary network was dismantled in June, 2003. The data from the dense network should give seismologists a better idea of the Denali Fault’s character. The estimated magnitude of this earthquake ranges from the body wave magnitude mb of 7.0 to the moment magnitude MW of 7.9 to the surface wave magnitude MS of 8.5. The locations of the Nenana Mountain and Denali Fault earthquakes and their aftershocks were determined by the Alaska Earthquake Information Center (AEIC) at the University of Alaska Fairbanks. One facility that was badly damaged by the earthquake was the runway at Northway Airport, 40 miles from the eastern part of the November 3, 2002, fault rupture. Although comparable in size and type to the quake that devastated San Francisco in 1906, the Denali Fault earthquake caused no deaths and little damage to structures because it struck a sparsely populated region of south-central Alaska. Called the Denali Fault earthquake, this shock was the strongest ever recorded in the interior of Alaska. This event caused significant damage to the transportation systems in central Alaska. Multiple land slides and rock avalanches occurred in the Alaska Range with the largest slide on the Black Rapids Glacier. In contrast, the 1994 Northridge, California, earthquake, which had the same magnitude, caused 67 deaths and $40 billion in damage when it struck the densely populated Los Angeles region. These effects were the result of a phenomenon called "liquefaction," in which strong, prolonged earthquake shaking transforms loose, water-saturated sediments into a liquid slurry. The Trans-Alaska Pipeline suffered some damage, but no oil spills occurred. Here a video about the 1964 Alaskan earthquake, also known as the Great Alaskan earthquake and Good Fr… By studying earthquakes like the 2002 Denali Fault earthquake, scientists and engineers gain the knowledge necessary to reduce the vulnerability of buildings and other structures to damage in these inevitable and terrifying events. The earthquake began at 1:12 p.m. Alaska local time, and was centered approximately 135 kilometers (84 miles) south of Fairbanks and 283 kilometers (176 miles) north of Anchorage. Following the Denali Fault earthquake, the analyst processing load increased from an average of 40 events per day in September to an average of over 400 events per day in November. This places the rupture in the same class as those that produced the San Andreas fault's two historical great earthquakes in 1906 and 1857. Four month of data remain unprocessed at this time (January-April, 2003). The principal rupture was a 210-kilometer-long section of the Denali fault, with horizontal shifts of up to nearly 9 meters (26 feet). USGS studies of the Denali Fault earthquake are part of the National Earthquake Hazard Reduction Program's ongoing efforts to safeguard lives and property from the future quakes that are certain to strike in Alaska, California, and elsewhere in the United States. This event was followed by numerous aftershocks that defined a 45-km-long zone along the Denali fault. While on average for October-December data mc is 1.4, it is as low as 1.1 at the western end of the rupture and as high as 2.2 at the eastern end. It illuminates earthquake mechanics and hazards of large strike-slip faults. They also located major landslides caused by the quake. 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