Denali earthquake

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Date and timeMag
DepthNearest volcano (distance)LocationDetailsMapThursday, October 21, 2021 15:05 GMT (11 earthquakes)Oct 21, 2021 7:05 am (GMT -8) (Oct 21, 2021 15:05 GMT)
83 km (52 mi)99 Km WNW of Skwentna, Alaska MoreMapOct 21, 2021 4:09 am (GMT -8) (Oct 21, 2021 12:09 GMT)

55 km141 km (88 mi)71 Km SSE of Cantwell, Alaska MoreMapOct 21, 2021 1:35 am (GMT -8) (Oct 21, 2021 09:35 GMT)

106 km150 km (93 mi)66 Km NNE of Petersville, Alaska MoreMapOct 21, 2021 1:11 am (GMT -8) (Oct 21, 2021 09:11 GMT)

91 km85 km (53 mi)Central Alaska MoreMapOct 21, 2021 12:41 am (GMT -8) (Oct 21, 2021 08:41 GMT)

72 km139 km (86 mi)9 Km N of Petersville, Alaska MoreMapOct 20, 2021 10:56 pm (GMT -8) (Oct 21, 2021 06:56 GMT)
82 km (51 mi)Central Alaska MoreMapOct 20, 2021 7:32 pm (GMT -8) (Oct 21, 2021 03:32 GMT)

57 km150 km (93 mi)59 Km NE of Chase, Alaska MoreMapOct 20, 2021 7:28 pm (GMT -8) (Oct 21, 2021 03:28 GMT)

52 km147 km (91 mi)61 Km NE of Chase, Alaska MoreMapOct 20, 2021 4:49 pm (GMT -8) (Oct 21, 2021 00:49 GMT)

0.1 km196 km (122 mi)51 Km S of Tanana, Alaska MoreMapOct 20, 2021 4:31 pm (GMT -8) (Oct 21, 2021 00:31 GMT)

103 km162 km (101 mi)53 Km NNW of Petersville, Alaska MoreMapOct 20, 2021 4:19 pm (GMT -8) (Oct 21, 2021 00:19 GMT)

82 km45 km (28 mi)44 Km E of Denali Park, Alaska MoreMapWednesday, October 20, 2021 22:40 GMT (8 earthquakes)Oct 20, 2021 2:40 pm (GMT -8) (Oct 20, 2021 22:40 GMT)

7.5 km122 km (76 mi)53 Km E of Denali National Park, Alaska MoreMapOct 20, 2021 9:52 am (GMT -8) (Oct 20, 2021 17:52 GMT)

7.8 km158 km (98 mi)Central Alaska MoreMapOct 20, 2021 7:41 am (GMT -8) (Oct 20, 2021 15:41 GMT)

5.5 km67 km (42 mi)27 Km ENE of Cantwell, Alaska MoreMapOct 20, 2021 3:47 am (GMT -8) (Oct 20, 2021 11:47 GMT)

55 km134 km (83 mi)70 Km SE of Cantwell, Alaska MoreMapOct 20, 2021 2:25 am (GMT -8) (Oct 20, 2021 10:25 GMT)

126 km138 km (86 mi)71 Km ESE of Denali National Park, Alaska MoreMapOct 20, 2021 1:35 am (GMT -8) (Oct 20, 2021 09:35 GMT)

4.5 km93 km (58 mi)7 Km NW of Harding-Birch Lakes, Alaska MoreMapOct 20, 2021 12:45 am (GMT -8) (Oct 20, 2021 08:45 GMT)

54 km144 km (89 mi)Central Alaska MoreMapOct 20, 2021 12:42 am (GMT -8) (Oct 20, 2021 08:42 GMT)
70 km (43 mi)60 Km ENE of Cantwell, Alaska MoreMapTuesday, October 19, 2021 19:48 GMT (12 earthquakes)Oct 19, 2021 11:48 am (GMT -8) (Oct 19, 2021 19:48 GMT)

115 km159 km (99 mi)50 Km NNW of Petersville, Alaska MoreMapOct 19, 2021 10:29 am (GMT -8) (Oct 19, 2021 18:29 GMT)
164 km (102 mi)47 Km SE of Denali National Park, Alaska MoreMapOct 19, 2021 3:19 am (GMT -8) (Oct 19, 2021 11:19 GMT)

1 km145 km (90 mi)69 Km S of Cantwell, Alaska MoreMapOct 19, 2021 3:01 am (GMT -8) (Oct 19, 2021 11:01 GMT)

9.9 km159 km (99 mi)6 Km NNE of Chase, Alaska MoreMapOct 19, 2021 2:27 am (GMT -8) (Oct 19, 2021 10:27 GMT)

4.6 km59 km (37 mi)12 Km SSW of Nenana, Alaska MoreMapOct 19, 2021 12:18 am (GMT -8) (Oct 19, 2021 08:18 GMT)

88 km108 km (67 mi)36 Km WSW of Cantwell, Alaska MoreMapOct 19, 2021 12:06 am (GMT -8) (Oct 19, 2021 08:06 GMT)

72 km167 km (104 mi)Matanuska-Susitna Parish, 100 mi north of Alaska City, Anchorage, Alaska, USA
I FELT IT - 6 reportsMoreMapOct 18, 2021 10:01 pm (GMT -8) (Oct 19, 2021 06:01 GMT)

83 km120 km (75 mi)40 Km SSW of Cantwell, Alaska MoreMapOct 18, 2021 9:05 pm (GMT -8) (Oct 19, 2021 05:05 GMT)

81 km91 km (57 mi)30 Km N of Skwentna, Alaska MoreMapOct 18, 2021 7:28 pm (GMT -8) (Oct 19, 2021 03:28 GMT)
171 km (106 mi)55 Km SSE of Denali National Park, Alaska MoreMapOct 18, 2021 4:56 pm (GMT -8) (Oct 19, 2021 00:56 GMT)

117 km160 km (99 mi)65 Km N of Petersville, Alaska MoreMapOct 18, 2021 4:48 pm (GMT -8) (Oct 19, 2021 00:48 GMT)

88 km96 km (60 mi)27 Km W of Cantwell, Alaska MoreMapMonday, October 18, 2021 22:27 GMT (12 earthquakes)Oct 18, 2021 2:27 pm (GMT -8) (Oct 18, 2021 22:27 GMT)

140 km90 km (56 mi)52 Km WSW of Denali Park, Alaska MoreMapOct 18, 2021 10:39 am (GMT -8) (Oct 18, 2021 18:39 GMT)

8.1 km150 km (93 mi)28 Km ESE of Denali National Park, Alaska MoreMapOct 18, 2021 6:12 am (GMT -8) (Oct 18, 2021 14:12 GMT)
171 km (106 mi)53 Km SSE of Denali National Park, Alaska MoreMapOct 18, 2021 5:24 am (GMT -8) (Oct 18, 2021 13:24 GMT)
71 km (44 mi)71 Km ESE of Denali Park, Alaska MoreMapOct 18, 2021 3:46 am (GMT -8) (Oct 18, 2021 11:46 GMT)

6.5 km197 km (122 mi)70 Km N of Lake Minchumina, Alaska MoreMapOct 18, 2021 3:31 am (GMT -8) (Oct 18, 2021 11:31 GMT)

39 km165 km (103 mi)16 Km ENE of Susitna North, Alaska 1 reportMoreMapOct 18, 2021 2:39 am (GMT -8) (Oct 18, 2021 10:39 GMT)
210 km (130 mi)62 Km NNW of Lake Minchumina, Alaska MoreMapOct 18, 2021 2:00 am (GMT -8) (Oct 18, 2021 10:00 GMT)

7.4 km161 km (100 mi)29 Km NE of Petersville, Alaska MoreMapOct 18, 2021 12:39 am (GMT -8) (Oct 18, 2021 08:39 GMT)

3.9 km127 km (79 mi)50 Km E of Denali National Park, Alaska MoreMapOct 18, 2021 12:25 am (GMT -8) (Oct 18, 2021 08:25 GMT)

92 km165 km (103 mi)45 Km N of Petersville, Alaska MoreMapOct 17, 2021 11:21 pm (GMT -8) (Oct 18, 2021 07:21 GMT)

8.6 km130 km (81 mi)62 Km SSE of Cantwell, Alaska MoreMapOct 17, 2021 9:58 pm (GMT -8) (Oct 18, 2021 05:58 GMT)

15 km130 km (81 mi)60 Km SSE of Cantwell, Alaska MoreMapSunday, October 17, 2021 19:58 GMT (9 earthquakes)Oct 17, 2021 11:58 am (GMT -8) (Oct 17, 2021 19:58 GMT)

8.7 km135 km (84 mi)5 Km SSW of Trapper Creek, Alaska MoreMapOct 17, 2021 10:25 am (GMT -8) (Oct 17, 2021 18:25 GMT)

27 km85 km (53 mi)16 Km NW of Four Mile Road, Alaska MoreMapOct 17, 2021 10:23 am (GMT -8) (Oct 17, 2021 18:23 GMT)

29 km85 km (53 mi)16 Km NW of Four Mile Road, Alaska MoreMapOct 17, 2021 4:16 am (GMT -8) (Oct 17, 2021 12:16 GMT)

66 km111 km (69 mi)48 Km SE of Cantwell, Alaska MoreMapOct 17, 2021 3:14 am (GMT -8) (Oct 17, 2021 11:14 GMT)

94 km28 km (17 mi)17 Km E of Healy, Alaska MoreMapOct 17, 2021 3:06 am (GMT -8) (Oct 17, 2021 11:06 GMT)

80 km160 km (99 mi)33 Km N of Petersville, Alaska MoreMapOct 16, 2021 9:28 pm (GMT -8) (Oct 17, 2021 05:28 GMT)

109 km32 km (20 mi)8 Km ESE of Healy, Alaska MoreMapOct 16, 2021 9:10 pm (GMT -8) (Oct 17, 2021 05:10 GMT)

58 km174 km (108 mi)27 Km NE of Chase, Alaska MoreMapOct 16, 2021 6:00 pm (GMT -8) (Oct 17, 2021 02:00 GMT)

63 km77 km (48 mi)38 Km WSW of Denali Park, Alaska MoreMapSaturday, October 16, 2021 22:03 GMT (8 earthquakes)Oct 16, 2021 2:03 pm (GMT -8) (Oct 16, 2021 22:03 GMT)

78 km103 km (64 mi)29 Km SW of Petersville, Alaska MoreMapOct 16, 2021 11:31 am (GMT -8) (Oct 16, 2021 19:31 GMT)

107 km157 km (98 mi)48 Km NNW of Petersville, Alaska MoreMapOct 16, 2021 9:08 am (GMT -8) (Oct 16, 2021 17:08 GMT)

123 km161 km (100 mi)56 Km NNW of Petersville, Alaska MoreMapOct 16, 2021 6:10 am (GMT -8) (Oct 16, 2021 14:10 GMT)

108 km97 km (60 mi)64 Km NW of Skwentna, Alaska MoreMapOct 16, 2021 2:24 am (GMT -8) (Oct 16, 2021 10:24 GMT)

23 km85 km (53 mi)17 Km N of Four Mile Road, Alaska MoreMapOct 16, 2021 1:25 am (GMT -8) (Oct 16, 2021 09:25 GMT)

129 km149 km (93 mi)62 Km SE of Denali National Park, Alaska MoreMapOct 16, 2021 12:52 am (GMT -8) (Oct 16, 2021 08:52 GMT)

5.7 km152 km (94 mi)25 Km ESE of Denali National Park, Alaska
I FELT ITMoreMapOct 15, 2021 4:39 pm (GMT -8) (Oct 16, 2021 00:39 GMT)

57 km154 km (96 mi)63 Km ENE of Chase, Alaska MoreMapFriday, October 15, 2021 20:00 GMT (8 earthquakes)Oct 15, 2021 12:00 pm (GMT -8) (Oct 15, 2021 20:00 GMT)

77 km130 km (81 mi)58 Km WSW of Cantwell, Alaska MoreMapOct 15, 2021 12:00 pm (GMT -8) (Oct 15, 2021 20:00 GMT)

29 km80 km (50 mi)72 Km E of Cantwell, Alaska MoreMapOct 15, 2021 10:46 am (GMT -8) (Oct 15, 2021 18:46 GMT)

122 km142 km (88 mi)Denali Parish, 141 mi southwest of Fairbanks, Alaska, USAMoreMapOct 15, 2021 9:59 am (GMT -8) (Oct 15, 2021 17:59 GMT)

19 km81 km (50 mi)12 Km NW of Four Mile Road, Alaska MoreMapOct 15, 2021 9:07 am (GMT -8) (Oct 15, 2021 17:07 GMT)
173 km (107 mi)54 Km SSE of Denali National Park, Alaska MoreMapOct 15, 2021 4:34 am (GMT -8) (Oct 15, 2021 12:34 GMT)

44 km182 km (113 mi)Central Alaska MoreMapOct 14, 2021 9:32 pm (GMT -8) (Oct 15, 2021 05:32 GMT)

77 km161 km (100 mi)33 Km N of Petersville, Alaska MoreMapOct 14, 2021 5:47 pm (GMT -8) (Oct 15, 2021 01:47 GMT)

94 km145 km (90 mi)68 Km NNE of Petersville, Alaska MoreMap
Sours: https://www.volcanodiscovery.com/

link to main US Geological Survey website

U.S. Geological Survey
Fact Sheet 014-03

Rupture in South-Central Alaska—The Denali Fault Earthquake of 2002

A powerful magnitude 7.9 earthquake struck Alaska on November 3, 2002, rupturing the Earth's surface for 209 miles along the Susitna Glacier, Denali, and Totschunda Faults. Striking a sparsely populated region, it caused thousands of landslides but little structural damage and no deaths. Although the Denali Fault shifted about 14 feet beneath the Trans-Alaska Oil Pipeline, the pipeline did not break, averting a major economic and environmental disaster. This was largely the result of stringent design specifications based on geologic studies done by the U.S. Geological Survey (USGS) and others 30 years earlier. Studies of the Denali Fault and the 2002 earthquake will provide information vital to reducing losses in future earthquakes in Alaska, California, and elsewhere.


Shortly after midday on November 3, 2002, a magnitude 7.9 earthquake ruptured the Denali Fault in the rugged Alaska Range, about 90 miles south of Fairbanks. Called the Denali Fault earthquake, this shock was the strongest ever recorded in the interior of Alaska. 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.

shaded relief map showing location and magnitudeof the main Denali Fault earthquake and all of its aftershocks
The November 3, 2002, magnitude (M) 7.9 Denali Fault earthquake was the strongest ever recorded in the interior of Alaska. Like most earthquakes of its size, it was complex, consisting of several subevents. It started with thrust (upward) motion on a previously unknown fault, now called the Susitna Glacier Fault. This rupture continued on the Denali Fault, where largely horizontal "right-lateral" movement (in which the opposite side moves to the right, when you look across the fault) propagated eastward at more than 7,000 miles per hour. As the rupture propagated, it offset streams, glacial ice, frozen soil, and rock, opening some cracks so wide that they could engulf a bus. The rupture crossed beneath the Trans-Alaska Oil Pipeline and terminated on the Totschunda Fault, 184 miles east of the epicenter, about 90 seconds after the quake began. The maximum horizontal movement (fault offset) of about 29 feet occurred in the eastern part of the rupture, near subevent 3.
index map of Alaska showing the oil pipeline, the area of fault rupture, and area of larger map


This powerful shock may have been triggered by a magnitude 6.7 temblor, the Nenana Mountain earthquake, that occurred nearby on the same fault 10 days earlier. Like the Denali Fault quake, the Nenana Mountain shock caused only limited damage because of its remote location. 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.

Effects of the Denali Fault Quake

The Denali Fault earthquake ruptured the Earth's surface for 209 miles, crossing beneath the vital Trans-Alaska Oil Pipeline, which carries 17% of the U.S. domestic oil supply. Although slightly damaged by movement on the fault and by intense shaking, the pipeline did not break in the quake, averting a major economic and environmental disaster. This success is a major achievement in U.S. efforts to reduce earthquake losses.

Violent, prolonged shaking from the quake triggered thousands of landslides, especially on the steep slopes of the Alaska Range. Mountainsides gave way, burying the valleys and glaciers below in deposits of rock and ice as much as 15 feet thick. The majority of landslides clustered in a narrow band extending about 8 to 12 miles on either side of the rupture.
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. The runway was rendered unusable by lateral spreading, accompanied by sand boils. 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. Areas that experienced liquefaction during the earthquake include much of the Tanana River Valley north and east of the rupture and other locations near smaller rivers.
Like some other large earthquakes, the Denali Fault quake triggered small shocks as far as 2,000 miles away, mainly in volcanic areas. Yellowstone National Park had the most energetic swarm of triggered earthquakes. Following the Denali Fault earthquake, Lake Union in Seattle experienced an earthquake-induced seiche, or water sloshing, which knocked many houseboats off their moorings and caused minor damage. Seiches were seen as far away as Lake Pontchartrain in Louisiana.

photograph of huge landslide in the Alaska Range that was triggered by the Denali Fault earthquake on November 3, 2002This huge landslide from an unnamed 7,000-foot-high peak in the Alaska Range, less than 10 miles west of the Trans-Alaska Oil Pipeline, was triggered by the 2002 Denali Fault earthquake. The fault rupture offset the ice of the mile-wide Black Rapids Glacier, in the foreground, which the landslide subsequently covered.

Documenting the Quake

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. AEIC receives data from more than 370 seismic stations, integrating all seismic networks in Alaska. A few of these stations are part of the new Advanced National Seismic System (ANSS) being deployed by the USGS and cooperators. After the Nenana Mountain earthquake, AEIC installed several temporary seismographs, including some ANSS instruments. When the Denali Fault earthquake struck a few days later, these stations helped to provide crucial data. Additional instruments were deployed after the Denali Fault quake, and as of December 2002, a total of 26 temporary seismic stations were gathering data on the quake's aftershocks.

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. They identified the previously unknown Susitna Glacier Fault in the area where the quake began and showed that the rest of the rupture exactly followed an older rupture that geologists had documented in the 1970's. They also located major landslides caused by the quake. The pattern of landsliding may help to better estimate levels of shaking along the length of the fault, especially because of the sparsity of seismic instruments in this rugged mountainous region.

Implications for Future Quakes Elsewhere

Because the 2002 Denali Fault earthquake occurred on a "strike-slip" fault, like the San Andreas Fault, it offers a realistic example of effects likely to accompany the next major earthquake in California. The Denali Fault quake is similar to three earthquakes that ruptured the San Andreas Fault in the past few centuries. These include the magnitude 7.8 San Francisco earthquake in 1906, the magnitude 7.9 Fort Tejon earthquake in 1857 north of Los Angeles, and a quake that struck east of what is now Los Angeles in about 1685. Evidence of the 1685 earthquake was only discovered in the past 20 years.

The 1857 California and 2002 Alaska earthquakes struck far from major cities, causing little or no loss of life. However, the 1906 earthquake near San Francisco killed at least 700 people (the actual death toll was probably 3 to 4 times greater). 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. Should such a quake occur today, San Bernardino, Los Angeles, and other populations centers in southern California could suffer heavy damage and loss of life.

Lessons Learned and Future Opportunities

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. Instrumental recordings of ground motion near earthquakes like the Denali Fault quake are critical for improving engineering design, but such quakes do not occur often. Following the Denali Fault earthquake, adjacent fault segments have been stressed, increasing the likelihood of additional earthquakes on those segments. This presents a rare opportunity to catch a major earthquake in the act. However, full ANSS instrumentation on either end of the 2002 rupture is critical if this goal is to be achieved.
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. 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.

Compiled By Gary S. Fuis and Lisa A. Wald

Edited by James W. Hendley II and Peter H. Stauffer
Graphic design by Susan Mayfield, Sara Boore, Eleanor Omdahl, and J. Luke Blair; Web layout by Carolyn Donlin

COOPERATING ORGANIZATIONS
Alaska Division of Geological and Geophysical Surveys
Alaska Earthquake Information Center, Geophysical
Institute, University of Alaska Fairbanks
Alaska Volcano Observatory
Alyeska Pipeline Service Company
California Institute of Technology
Central Washington University
Humboldt State University
University of California Berkeley
West Coast and Alaska Tsunami Warning Center

For more information contact:
Earthquake Information Hotline (650) 329-4085
U.S. Geological Survey, Mail Stop 977
345 Middlefield Road, Menlo Park, CA 94025
Visit the USGS Earthquake Hazards Program website to learn more

PDF version of this fact sheet (2.2 MB)

REDUCING EARTHQUAKE LOSSES THROUGHOUT THE UNITED STATES

For questions about the content of this report, contact Gary Fuis

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URL of this page: https://pubs.usgs.gov/fs/2003/fs014-03/
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2002 Denali earthquake

7.9 magnitude; November 3, 2002

The 2002 Denali earthquake occurred at 22:12:41 UTC (1:12 PM Local Time) November 3 with an epicenter 66 km ESE of Denali National Park, Alaska, United States. This 7.9 Mw earthquake was the largest recorded in the United States in 37 years (after the 1965 Rat Islands earthquake). The shock was the strongest ever recorded in the interior of Alaska.[5] Due to the remote location, there were no fatalities and only one injury.

Due to the shallow depth, it was felt at least as far away as Seattle and it generated seiches on bodies of water as far away as Texas and New Orleans, Louisiana.[6] About 20 houseboats were damaged by a seiche on a lake in Washington State.[6]

Tectonic setting[edit]

The Denali-Totschunda fault is a major dextral (right lateral) strike-slip system, similar in scale to the San Andreas fault system. In Alaska, moving from east to west, the plate interactions change from a transform boundary between Pacific and North American plates to a collision zone with a microplate, the Yakutat terrane, which is in the process of being accreted to the North American plate, to a destructive boundary along the line of the Aleutian islands. The Denali-Totschunda fault system is one of the structures that accommodate the accretion of the Yakutat terrane.

Earthquake characteristics[edit]

On October 23, 2002, there was a magnitude 6.7 earthquake located on the Denali fault. Because of its location close to the November 3 event and the fact that it preceded it by only 11 days, this earthquake is regarded as a foreshock.[7] The calculated stress transfer from this foreshock indicates that is brought the Denali fault at the location of the mainshock epicenter closer to failure.[8]

The initial rupture on November 3 was on a thrust fault segment, the previously unknown Susitna Glacier thrust,[7][9] to the south of the Denali fault. The epicenter lies just 25 kilometers (16 mi) east of the October 23 foreshock. The rupture then jumped to the main Denali Fault strand propagating for a further 220 km (137 mi) before jumping again onto the Totschunda Fault and rupturing another 70 km (43 mi) of fault plane.[9] The total surface rupture was ca. 340 km (211 mi).

There is evidence of local supershear propagation inferred from ground motions.[10]

Earthquake damage[edit]

View of Trans-Alaska Pipeline showing deliberate offsets in construction, to accommodate movement on the fault

Minor damage was reported over a wide area but the only examples of severe damage were on highways that crossed the fault trace and areas that suffered liquefaction, e.g. Northway Airport.[11] Several bridges were damaged but none so severely that they were closed to traffic.

Due to the general self-sufficiency of those living near the fault rupture, very few lifeline systems were compromised. These people tend to get water from private wells, heat their homes and cook their meals with gas furnaces and stoves, and maintain individual septic systems.[11]

The Trans-Alaska Pipeline System crosses the rupture trace; the pipeline suffered some minor damage to supports. There was no oil spillage, as the pipeline at that location was designed to move laterally along beams to withstand major movement on the Denali Fault.[12] The pipeline was shut down for three days to allow for inspections but was then reopened.

See also[edit]

References[edit]

  1. ^ abISC (2016), ISC-GEM Global Instrumental Earthquake Catalogue (1900–2012), Version 3.0, International Seismological Centre
  2. ^"M 7.9 - 75 km East of Cantwell, Alaska".
  3. ^ abNational Geophysical Data Center / World Data Service (NGDC/WDS) (1972), Significant Earthquake Database (Data Set), National Geophysical Data Center, NOAA, doi:10.7289/V5TD9V7K
  4. ^Fuis, Gary S.; Wald, Lisa A. (February 5, 2003). "Fact Sheet 014-03: Rupture in South-Central Alaska—The Denali Fault Earthquake of 2002". U.S. Geological Survey. Retrieved 2008-07-20.
  5. ^ abRuppert, N. (2008). "M 7.9 Denali Fault earthquake of November 3, 2002". Alaska Earthquake Information Center. Archived from the original on 2016-02-17. Retrieved 2014-09-18.
  6. ^ abCrone, A.J.; Personius, S.F.; Craw, P.A.; Haeussler, P.J.; Staft, L.A. (2005). "The Susitna Glacier Thrust Fault: Characteristics of Surface Ruptures on the Fault that Initiated the 2002 Denali Fault Earthquake". Bulletin of the Seismological Society of America. 94 (6B): S5–S22. doi:10.1785/0120040619.
  7. ^Anderson, G.; Ji, C. (2003). "Static stress transfer during the 2002 Nenana Mountain-Denali Fault, Alaska, earthquake sequence". Geophysical Research Letters. 30 (6). doi:10.1029/2002GL016724.
  8. ^ abEberhart-Phillips, Donna; Haeussler, Peter J.; Freymueller, Jeffrey T.; Frankel, Arthur D.; Rubin, Charles M.; Craw, Patricia; Ratchkovski, Natalia A.; Anderson, Greg; Carver, Gary A.; Crone, Anthony J.; Dawson, Timothy E. (2003-05-16). "The 2002 Denali Fault Earthquake, Alaska: A Large Magnitude, Slip-Partitioned Event". Science. 300 (5622): 1113–1118. doi:10.1126/science.1082703. ISSN 0036-8075. PMID 12750512.
  9. ^Dunham, E. M.; Archuleta, R. J. (2004), "Evidence for a Supershear Transient during the 2002 Denali Fault Earthquake", Bulletin of the Seismological Society of America, 94 (6B): 256–268, Bibcode:2004BuSSA..94S.256D, doi:10.1785/0120040616
  10. ^ abMark Yashinsky, ed. (2004). Denali, Alaska, Earthquake of November 3, 2002. Reston, VA: ASCE, TCLEE. ISBN . Archived from the original on 2013-12-31.
  11. ^Sorensen, S.P. and Meyer, K.J.: Effect of the Denali Fault Rupture on the Trans-Alaska PipelineArchived 2011-05-14 at the Wayback Machine; Sixth U.S. Conference and Workshop on Lifeline Earthquake Engineering, ASCE, August 2003.

External links[edit]

←Earthquakes in 2002→

  • Afyon (6.5, Feb 3)
  • Hindu Kush (7.4/6.1, Mar 3/25)
  • Mindanao (7.5, Mar 5)
  • Hualien (7.1, Mar 31)
  • Tbilisi (4.8, April 25)
  • Bou'in-Zahra (6.5, Jun 22)
  • Burica Peninsula (6.5, Jul 30)
  • Kalehe (6.2, Oct 24)
  • Molise (5.9, Oct 31)
  • Simeulue, Indonesia (7.3, Nov 2)
  • Denali (7.9, Nov 3)

indicates earthquake resulting in at least 30 deaths
indicates the deadliest earthquake of the year

Sours: https://en.wikipedia.org/wiki/2002_Denali_earthquake

Moderate mag. 3.7 earthquake - Denali Parish, 8.6 mi north of Healy, Denali, Alaska, USA, on Sunday, Feb 14, 2021 10:47 am (GMT -9) -

I felt this quake

Quake Data | Interactive map | User Reports | Earlier quakes here | Quakes in the US | Alaska

Moderate mag. 3.7 earthquake - Denali Parish, 8.6 mi north of Healy, Denali, Alaska, USA, on Sunday, Feb 14, 2021 10:47 am (GMT -9)

Moderate magnitude 3.7 earthquake at 6 km depth

14 Feb 19:50 UTC: First to report: USGS after 4 minutes.
14 Feb 19:52: Hypocenter depth recalculated from 7.1 to 7.3 km (from 4.4 to 4.5 mi).
... [show all] ...14 Feb 19:54: Hypocenter depth recalculated from 7.3 to 7.5 km (from 4.5 to 4.7 mi).
14 Feb 19:56: Hypocenter depth recalculated from 7.5 to 7.3 km (from 4.7 to 4.5 mi).
14 Feb 19:57: Magnitude recalculated from 3.8 to 3.9. Hypocenter depth recalculated from 7.3 to 7.4 km (from 4.5 to 4.6 mi).
14 Feb 19:59: Hypocenter depth recalculated from 7.4 to 8.5 km (from 4.6 to 5.3 mi).
14 Feb 20:01: Hypocenter depth recalculated from 8.5 to 7.7 km (from 5.3 to 4.8 mi).
14 Feb 20:10: Magnitude recalculated from 3.9 to 3.7. Hypocenter depth recalculated from 7.7 to 6.1 km (from 4.8 to 3.8 mi). Epicenter location corrected by 8.3 km (5.2 mi) towards S.

Update Sun, 14 Feb 2021, 19:54

Magnitude 3.8 earthquake strikes near Healy, Denali County, Alaska, USA
3.8 quake 14 Feb 10:47 am (GMT -9)

3.8 quake 14 Feb 10:47 am (GMT -9)

the United States Geological Survey reported a magnitude 3.8 quake in the United States near Healy, Denali County, Alaska, only 7 minutes ago. The earthquake hit in the morning on Sunday 14 February 2021 at 10:47 am local time at a very shallow depth of 4.5 miles. The exact magnitude, epicenter, and depth of the quake might be revised within the next few hours or minutes as seismologists review data and refine their calculations, or as other agencies issue their report.
A second report was later issued by the European-Mediterranean Seismological Centre (EMSC), which listed it as a magnitude 3.8 earthquake as well.
Based on the preliminary seismic data, the quake should not have caused any significant damage, but was probably felt by many people as light vibration in the area of the epicenter.
Weak shaking might have been felt in Ferry (pop. 33) located 6 miles from the epicenter, and Healy (pop. 1000) 14 miles away.

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Earthquake data

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Date & time:Feb 14, 2021 19:47:05 UTC -
Local time at epicenter:Sunday, Feb 14, 2021 10:47 am (GMT -9)
Magnitude: 3.7
Depth: 6.1 km
Epicenter latitude / longitude: 63.9812°N / 148.9532°W↗ (Denali, Alaska, United States)
Antipode: 63.981°S / 31.047°E↗
Nearest volcano: Buzzard Creek(28 km / 17 mi)
Nearby towns and cities:
9 km (6 mi) ESE of Ferry(pop: 33) --> See nearby quakes!
14 km (9 mi) N of Healy(pop: 1,020) --> See nearby quakes!
28 km (17 mi) N of McKinley Park(pop: 185) --> See nearby quakes!
42 km (26 mi) SSE of Anderson(pop: 265) --> See nearby quakes!
112 km (70 mi) SSW of College(pop: 13,000) --> See nearby quakes!
112 km (70 mi) SSW of Fairbanks(pop: 32,300) --> See nearby quakes!
114 km (71 mi) SW of Badger(pop: 19,500) --> See nearby quakes!
297 km (185 mi) N of Eagle River(pop: 24,800) --> See nearby quakes!
297 km (185 mi) N of Eagle River (Anchorage)(pop: 24,800) --> See nearby quakes!
1000 km (621 mi) NW of Juneau(pop: 32,800) --> See nearby quakes!
Weather at epicenter at time of quake:
Clear Sky -27.2°C(-17 F), humidity: 70%, wind: 2 m/s (4 kts) from SSE
Primary data source:USGS (United States Geological Survey)
Estimated released energy:2.2 x 1010joules (6.22 megawatt hours, equivalent to 5.35 tons of TNT) More info

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Data for the same earthquake reported by different agencies

Info: The more agencies report about the same quake and post similar data, the more confidence you can have in the data. It takes normally up to a few hours until earthquake parameters are calculated with near-optimum precision.

Mag.DepthLocationSource
3.76.1 km8 Km ESE of Ferry, Alaska, USAUSGS
4.012 kmCENTRAL ALASKA, USAEMSC

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Earthquake denali

a map that shows the number of earthquakes that took place in and around Denali from 2007-2011

With more than 20,000 earthquakes reported annually, Alaska is by far the most seismically active state. Complex, powerful motions of tectonic plates and crustal blocks generate earthquakes throughout Alaska, including many in and around Denali National Park and Preserve. Alaska not only experiences the most earthquakes in the United States, but also the strongest. The Good Friday Earthquake—a 1964 magnitude 9.2 event located in Prince William Sound—remains the largest earthquake ever recorded in the U.S. and the secondlargest earthquake ever recorded worldwide.

Seismic station in Denali with antenna, solar panel, and equipment hut.

Alaska Earthquake Information Center

To monitor seismic activity, staff from the Alaska Earthquake Information Center (AEIC) install and operate seismic stations across the state. Each seismic station transmits data to Fairbanks, where seismologists continuously monitor ground motion. Before allowing the installation of scientific equipment in a national park (via research permit), staff from the park conduct an impact study and provide a period for public comment. AEIC has four seismic stations in Denali: (from west to east, see map) Castle Rocks (CAST), Kantishna Hills (KTH) on Wickersham Dome, Thoroughfare Mountain (TRF), and McKinley (MCK) near the park entrance.

Seismometer in an underground vault that reduces

Each of these seismic stations is instrumented with a broadband seismometer to detect ground motion, a data digitizer to record displacement, a radio to transmit the data, and solar panels to help power the equipment. In addition, CAST, KTH, and MCK are instrumented with accelerometers to measure ground acceleration. To send these continuous ground motion data to a central location for analysis, AEIC also operates radio repeaters within the park at Double Mountain, Mount Healy, and the Murie Science and Learning Center.

AEIC employee monitoring earthquakes in front of a computer.

Was That an Earthquake?

Real time ground motion data from ~400 seismic stations across the state are used to identify and characterize each earthquake in Alaska. Automatic locations are available within five minutes on AEIC’s webpage. If the automatic location algorithms indicate a large earthquake, the seismologist on duty responds immediately (seismologists are on call 24/7) and issues an information release—in part to help emergency management personnel respond to significant events. Every event is briefly reviewed by the on-duty seismologist, and carefully relocated by an analyst. Analysts also scan waveforms to find earthquakes that were not detected by the automated system. AEIC analysts locate between 20,000 and 30,000 earthquakes in Alaska each year.

Where do Earthquakes Occur in the Park?

Earthquakes shake the ground daily, but most are minor local events. Seismicity in interior Alaska north of the Denali fault is dominated by shallow events (see blue dots on map above). Note how the blue dots scattered at the top of the map track roughly northeast-trending parallel lines. These lines are shear zones where smaller crustal blocks are shifting between major faults. Movement at shear zones have generated up to magnitude (M) 7.3 earthquakes. The Kantishna cluster is a group of small, shallow earthquakes—not far from Wonder Lake—at the southwestern end of a shear zone. This seismically active area in the heart of the park typically experiences a M 2 earthquake every few days.

Deep earthquakes occur under the ground in the southern and eastern portions of the park (see red-orange and orange dots on the map above). These quakes are associated with the northern extension of the subduction edge of the Pacific plate and its dive beneath the North American crust. The Pacific plate is moving northwest relative to Alaska, causing many earthquakes along the interface. The pattern of shallow, intermediate, and deep events in south-central Alaska highlights the shallow angle of the subduction. In the Aleutian Islands, where the subduction angle is much steeper, the shallow-todeep earthquake pattern is more compact.

Earthquakes Outside the Park

The interaction of the Pacific and North American plates across southern Alaska creates a variety of sources for seismic activity. As crustal blocks slide horizontally past one another, strike slip faults occur; when blocks are pushed together, one block is thrust up or down along the fault line.

Great earthquakes (those with M greater than 8.0) typically occur along the Pacific-North American plate boundary far south of the park. The 1964 Good Friday Earthquake is an example.

Major earthquakes (those with a magnitude range of 7.0-7.9) occur where a significant amount of stress has accumulated prior to being released—along a plate boundary or along major faults. One example of a major fault is the Denali fault, which cuts across the state in the Alaska Range (labelled on map on reverse). In 2002, the M 7.9 earthquake ruptured a portion of the Denali fault east of the park to produce a horizontal offset of up to 8.8 m (29 feet). The main shock occurred about 80 km (50 miles) east of the Denali Visitor Center. In the months that followed, roughly 25,000 aftershocks were located on the Denali and Totshunda faults, revealing a surface rupture that was 325 km (200 miles) long.

Is Denali Waiting for the Big One?

The section of the Denali fault cutting across the park has not experienced a major earthquake within the last ~100 years. The more stress that builds up across a fault, the larger the earthquake is when that stress is released. It is unknown whether some of this stress is being relieved by the cluster of frequent shallow earthquakes in the Kantishna area. As the stress mounts along the Denali fault in the park, and as more time elapses without the stress release of a strong earthquake, the probability of a big earthquake in the park continues to rise.

a map that shows earthquakes all across Alaska, the earthquakes arc through the state
Sours: https://www.nps.gov/articles/denali-earthquake-monitoring.htm

Denali Fault

Denali Fault
LocationBritish Columbia, Canada and Alaska, USA
PlateNorth American Plate
Earthquakes2002 Denali earthquake
Typedextral strike-slip fault
Tectonic map of Alaska and northwestern Canada showing main faults and historic earthquakes
Denali Fault and the Denali National Park boundary

The Denali Fault is a major intracontinental dextral (right lateral) strike-slip fault in western North America, extending from northwestern British Columbia, Canada to the central region of the U.S. state of Alaska.[1]

Location[edit]

The Denali Fault is located in Alaska's Denali National Park and to the east. This National Park includes part of a massive mountain range more than 600 miles long. Along the Denali Fault, lateral and vertical offset movement is taking place.

The steep north face of Denali, known as the Wickersham Wall, rises 15,000 feet from its base, and is a result of this relatively recent movement.[citation needed]

Effects[edit]

Alaska's network of faults is a result of tectonic activity; the Pacific Plate is actively subducting (sliding under) the North American Plate, and the Denali Fault is located on the boundary between the two plates.[2] The fault's rate of displacement varies from 1 mm to 35 mm per year.[3]

It was the main fault along which the 2002 Denali earthquake occurred, which was measured as a magnitude of 7.9 Mw.[4] During the afternoon of November 3, 2002, the water in Seattle's Lake Union suddenly began sloshing hard enough to knock houseboats off their moorings. Water in pools, ponds, and bayous as far away as Texas and Louisiana splashed for nearly half an hour.[citation needed]

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. Shaking at the epicenter lasted approximately 1.5 to 2 minutes, but in Fairbanks the duration of the earthquake was over 3 minutes.[citation needed]

Originating on the previously unknown Susitna Glacier Fault, the earthquake shot eastward along the well-known Denali Fault at a speed of over 11,265 kilometers (7,000 miles) per hour before branching southeast onto the Totschunda Fault. The resulting surface rupture was approximately 336 kilometers (209 miles) long, and it cut through streams, divided forests, opened chasms in roads, and even generated fault traces visible across several glaciers. Because the earthquake released most of its energy on the sparsely populated eastern end of the fault, Alaska's major cities were spared serious damage.[2]

See also[edit]

References[edit]

  1. ^Benjamin R. Edwards, James K. Russell (August 2000). "Distribution, nature, and origin of Neogene–Quaternary magmatism in the northern Cordilleran volcanic province, Canada"(PDF). Geological Society of America Bulletin. 112 (8): 1280–1295. Bibcode:2000GSAB..112.1280E. doi:10.1130/0016-7606(2000)112<1280:dnaoon>2.0.co;2.
  2. ^ abLaura Naranjo (November 13, 2003). "Denali's Fault". NASA. Retrieved May 20, 2012.
  3. ^Mark Yashinsky, ed. (2004). Denali, Alaska, Earthquake of November 3, 2002. Reston, VA: ASCE, TCLEE. ISBN . Archived from the original on 2013-12-31.
  4. ^Eberhart-Phillips, Donna; Haeussler, Peter J.; Freymueller, Jeffrey T.; Frankel, Arthur D.; Rubin, Charles M.; Craw, Patricia; Ratchkovski, Natalia A.; Anderson, Greg; Carver, Gary A.; et al. (May 2003). "The 2002 Denali Fault Earthquake, Alaska: A Large Magnitude, Slip-Partitioned Event". Science. 300 (5622, number 5622): 1113–1118. Bibcode:2003Sci...300.1113E. doi:10.1126/science.1082703. PMID 12750512.
Sours: https://en.wikipedia.org/wiki/Denali_Fault

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Denali's Fault

Denali's Fault title

By Laura Naranjo

During the afternoon of November 3, 2002, the water in Seattle’s Lake Union suddenly began sloshing hard enough to knock houseboats off their moorings. Water in pools, ponds, and bayous as far away as Texas and Louisiana splashed for nearly half an hour. The cause? Alaska’s Denali Fault was on the move, jostling the state with a magnitude 7.9 earthquake.

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. Shaking at the epicenter lasted approximately 1.5 to 2 minutes, but in Fairbanks the duration of the earthquake was over 3 minutes.

Originating on the previously unknown Susitna Glacier Fault, the earthquake shot eastward along the well-known Denali Fault at a speed of over 11,265 kilometers (7,000 miles) per hour before branching southeast onto the Totschunda Fault. The resulting surface rupture was approximately 336 kilometers (209 miles) long, and it cut through streams, divided forests, opened chasms in roads, and even generated fault traces visible across several glaciers. Because the earthquake released most of its energy on the sparsely populated eastern end of the fault, Alaska’s major cities were spared serious damage.

Pacific Plate tectonic map

The November 3 Denali Fault earthquake was preceded by the magnitude 6.7 Nenana Mountain earthquake on October 23. Now considered a foreshock of the larger quake, the October earthquake caused no surface ruptures. Both quakes were centered along the Denali Fault.

Andrew Ford, a researcher at the University of Utah, was studying the fault system in southeast Alaska with colleagues Rick Forster and Ron Bruhn, both professors at the University of Utah. “When the earthquakes occurred, we wanted to see if we could determine how much ground motion there was,” said Ford.

Using a remote sensing technique called InSAR (Interferometric Synthetic Aperture Radar), Ford created a map of surface changes caused by the earthquake. Interferometry involves taking Synthetic Aperture Radar (SAR) satellite images from two different dates and precisely calculating the differences between the two. The resulting image, called an interferogram, shows where deformation occurred on the Earth’s surface. “Interferometry is a good way to locate faults and see which sections are susceptible to deformation,” said Evelyn Price, a research associate at the University of Texas Institute for Geophysics.

SAR Denali epicenters

In the past, scientists typically relied on SAR imagery from the European Remote Sensing (ERS) satellites, ERS-1 and ERS-2, to map earthquake deformation. But ERS-1 failed in 2000, and ERS-2 began malfunctioning shortly afterwards. So Ford and his colleagues turned to SAR imagery from RADARSAT-1 (a satellite managed by the Canadian Space Agency), which had never before been applied in earthquake interferometry.

One of the biggest challenges with SAR imagery is the infrequency of satellite observations. In that respect, RADARSAT-1 had an advantage over the ERS missions. “RADARSAT-1 repeats its orbit every 24 days, whereas ERS-1 and ERS-2 repeated every 35 days,” said Ford. Surface changes occurring between orbits (such as excessive rainfall or snowfall, or changes in vegetation) can cause “noise” in interferograms, making them less accurate. “The less time between repeat orbits, the less chance there is for change on the Earth’s surface,” said Ford.

After the November 3 earthquake, Ford and his colleagues contacted the Alaska Satellite Facility (ASF) in Fairbanks. “ASF gave us priority. Once the satellite acquired the image we needed, ASF downloaded and formatted it, and it was ready for us within hours,” said Ford. Fortunately, ASF had images from October 5 (prior to the foreshock earthquake), October 29 (between the two earthquakes), and November 22 (after the second earthquake) that included the area of both earthquakes’ epicenters.

ASF’s fortuitous collection of images allowed Ford and his colleagues to make a series of three interferograms: one for each of the earthquakes, and a cumulative interferogram that includes both earthquakes. “It’s the first time this has ever been done in earthquake research. Every pair of SAR images used in the past has straddled both the major foreshocks and the mainshock. Now we can actually separate the two quakes,” said Ford.

Suslina Glacier map

The ability to generate interferograms for each earthquake allowed Ford to investigate how the foreshock focused tectonic stresses and added strength to the mainshock. Because earthquakes tend to recur along faults, an earthquake that relieves stress on one part of a fault may actually increase stress on other parts of a fault system.

Alaska’s network of faults is a result of tectonic activity; the Pacific Plate is actively subducting (sliding under) the North American Plate, and the Denali Fault is located on the boundary between the two plates. Prior to the 2002 earthquakes, the Denali Fault was known to be seismically active, but scientists weren’t sure if it was capable of generating a large earthquake.

Because some of the faults in southeast Alaska are heavily glaciated, Ford and his colleagues are also interested in studying the relationship between glaciers and structural geology. Glaciers tend to flow down fault lines, eroding the ground surface and acting as conveyor belts for rock material. They also prevent material from filling in faults, which tends to keep faults active.

In addition, landslides completely covered parts of several Alaskan glaciers after the November 3 Denali Fault earthquake. Landslide material may insulate glacier ice, raising its temperature towards the melting point. The additional weight of rocks and dirt can also cause greater pressure and melting at the base of the glacier, increasing the likelihood that a glacier may surge forward. “We want to know how earthquakes affect the behavior of these glaciers and how the glaciers are moving and responding,” said Ford.

Augustana Creek fault scarp
Even though the earthquakes occurred in a sparsely populated area, scientists are keeping an eye on the Denali Fault because of its similarities to the San Andreas Fault, located near heavily populated areas in California. According to Ford, “The Denali Fault earthquake was the ‘big one’ for Alaska.” The cracks in the Earth’s surface along parts of the fault were up to 6.7 meters (22 feet) wide, which would have caused considerable damage to a more heavily populated area, such as California. While the November 3 earthquake in Alaska caused few injuries and no deaths, it did cause numerous landslides and damaged roads and bridges at a cost of at least $25 million.
Denali Fault trace run
In addition, both of the Denali Fault earthquakes occurred at a depth in the Earth’s crust of 5 kilometers (3.1 miles) or less, which is considered relatively shallow. “Usually, the earthquakes that are damaging to populations and structures occur close to the surface, so this is significant,” said Price. By further studying and understanding the kind of deformation that split open the ground surface in Alaska, scientists hope to glean clues about earthquake damage potential along the San Andreas Fault.

The InSAR maps of surface deformation near the earthquake epicenters that Ford and his colleagues generated agreed with USGS findings, which included aerial and ground surveys of the fault rupture, as well as Global Positioning System (GPS) measurements. Although Alaska’s Denali Fault was home to a network of GPS receivers, earthquakes are unpredictable, and no one knows whether the next one will strike in a location with a GPS receiver to measure it. “With InSAR, we can capture the whole picture, no matter where the epicenter of an earthquake is,” said Ford. “And you can’t measure ground motion on the scale of millimeters over that kind of area unless you use interferometry.”

References

Evelyn J. Price and David T. Sandwell. 1998. Small-scale deformations associated with the 1992 Landers, California, earthquake mapped by synthetic aperture radar interferometry phase gradients. Journal of Geophysical Research . 103(B11):27,001-27,016.

For more information

NASA Alaska Satellite Facility Distributed Active Archive Center (ASF DAAC)

About the remote sensing data used
SatellitesERS-1& 2
RADARSAT-1
Global Positioning System (GPS)
SensorsSynthetic Aperture Radar (SAR)
Interferometric SAR (InSAR)
Parameterearthquake deformation
DAACNASA Alaska Satellite Facility Distributed Active Archive Center (ASF DAAC)

Page Last Updated: Jul 21, 2020 at 7:28 PM EDT

Sours: https://earthdata.nasa.gov/learn/sensing-our-planet/denali-s-fault


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