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Can "MegaQuakes" really happen? Like a magnitude 10 or larger?
No, earthquakes of magnitude 10 or larger cannot happen. The magnitude of an earthquake is related to the length of the fault on which it occurs. That is, the longer the fault, the larger the earthquake. A fault is a break in the rocks that make up the Earth's crust, along which rocks on either side have moved past each other. No fault long enough to generate a magnitude 10 earthquake is known to exist, and if it did, it would extend around most of the planet.
The largest earthquake ever recorded was a magnitude 9.5 on May 22, 1960 in Chile on a fault that is almost 1,000 miles long… a “megaquake” in its own right.
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1964 Great Alaska Earthquake: a photographic tour of Anchorage, Alaska
On March 27, 1964, at 5:36 p.m., a magnitude 9.2 earthquake, the largest recorded earthquake in U.S. history, struck southcentral Alaska (fig. 1). The Great Alaska Earthquake (also known as the Good Friday Earthquake) occurred at a pivotal time in the history of earth science, and helped lead to the acceptance of plate tectonic theory (Cox, 1973;...
Thoms, Evan E.; Haeussler, Peter J.; Anderson, Rebecca D.; McGimsey, Robert G.
The 1964 Great Alaska Earthquake and tsunamis: a modern perspective and enduring legacies
The magnitude 9.2 Great Alaska Earthquake that struck south-central Alaska at 5:36 p.m. on Friday, March 27, 1964, is the largest recorded earthquake in U.S. history and the second-largest earthquake recorded with modern instruments. The earthquake was felt throughout most of mainland Alaska, as far west as Dutch Harbor in the Aleutian Islands...
Brocher, Thomas M.; Filson, John R.; Fuis, Gary S.; Haeussler, Peter J.; Holzer, Thomas L.; Plafker, George; Blair, J. Luke
The Global Seismographic Network
Gee, Lind S.; Leith, William S.
Predecessors of the giant 1960 Chile earthquake
It is commonly thought that the longer the time since last earthquake, the larger the next earthquake's slip will be. But this logical predictor of earthquake size, unsuccessful for large earthquakes on a strike-slip fault, fails also with the giant 1960 Chile earthquake of magnitude 9.5 (ref. 3). Although the time since the preceding earthquake...
Cisternas, M.; Atwater, B.F.; Torrejon, F.; Sawai, Y.; Machuca, G.; Lagos, M.; Eipert, A.; Youlton, C.; Salgado, I.; Kamataki, T.; Shishikura, M.; Rajendran, C.P.; Malik, J.K.; Rizal, Y.; Husni, M.
The USGS Earthquake Hazards Program - investing in a safer future
Filson, John R.; McCarthy, Jill; Ellsworth, William L.; Zoback, Mary Lou; Stauffer, Peter H.; Hendley, James W.
When will the next great quake strike northern California?
Thatcher, Wayne R.; Ward, Peter L.; Wald, David J.; Hendley, James W.; Stauffer, Peter H. Understand earthquake hazards
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Spall, Henry
Types of damage that could result from a great earthquake in the New Madrid, Missouri, seismic zone
In the winter of 1811–1812 a series of three great earthquakes occurred in the New Madrid seismic zone. In addition to the three principal shocks, at least 15 other earthquakes, Io ≥ VIII, occurred within a year of the first large earthquake on December 16, 1811. The three main shocks were felt over the entire eastern United States. They...
Hopper, M.G.; Algermissen, S.T.
Can a Creeping Segment of the Alaska-Aleutian Subduction Zone Generate a Great Earthquake?
The coastal geology of Simeonof Island, the southeastern-most island in the Shumagin archipelago of the Aleutian Islands, suggests the region has not experienced a great megathrust earthquake in at least the past 3,400 years.
Prior Great Earthquakes Unveiled at the Western Edge of the 1964 Alaska Rupture
Ever since the great magnitude 9.2 earthquake shook Alaska 50 years ago today, scientists have suspected that the quake's rupture halted at the southwestern tip of Kodiak Island due to a natural barrier.
USGS Updates Magnitude of Japan’s 2011 Tohoku Earthquake to 9.0
The USGS has updated the magnitude of the March 11, 2011, Tohoku earthquake in northern Honshu, Japan, to 9.0 from the previous estimate of 8.9. Independently, Japanese seismologists have also updated their estimate of the earthquake’s magnitude to 9.0.
What Would a Great Earthquake do to the Buildings in Downtown Los Angeles?
A great earthquake along the southern San Andreas Fault could cause many tall buildings to collapse in Los Angeles, explains USGS earthquake expert Dr. Ken Hudnut in a new video interview.
2004 Deadliest in Nearly 500 Years for Earthquakes
According to the U.S. Geological Survey (USGS), 2004 was the deadliest year for earthquakes since the Renaissance Age, making it the second most fatal in recorded history, with more than 275,950 deaths reported from the magnitude 9.0 earthquake and subsequent tsunami that hit the Indian Ocean on Dec. 26.
Mega Earthquake Not Likely For Southern California
Southern California is not likely to experience a "huge earthquake,"according to two scientists with the U.S. Geological Survey.
SUMATRA, INDONESIA EARTHQUAKE
A magnitude 7.0 earthquake occurred on southern Sumatra, Indonesia, at 2:09 p.m. EDT (local time on Sumatra 1:09 a.m., Oct. 7). The epicenter was about 105 miles southeast of Panang or 290 miles southwest of Singapore.
Cascadia Subduction Zone
Block diagram illustrating an idealized geological setting offshore the state of Washington. As the subducting Juan De Fuca tectonic plate dives beneath North America, it can generate an earthquake, and trigger a tsunami.
PubTalk 2/2014 — 1964 Great Alaska Earthquake and Tsunami 50th Anniv.
By George Plafker, USGS Geologist Emeritus
- March 27th, 1964, one of the most violent earthquakes of all time rocked southern Alaska.
- More than 50,000 square miles of the state was tilted to new elevation, and the resulting property damage disrupted the state's economy.
- Within 24 hours, a team of USGS geologists
Tohoku waterfront area, Japan
April 2011 in waterfront area of Tohoku, Japan following the March 11 2011 earthquake and tsunami.
PubTalk 4/2010 — Large, Destructive Earthquakes in Haiti and Chile
Lessons Learned for the San Francisco Bay Area
by USGS Geophysicists, Walter Mooney & Eric Geist
- Why was the January 2010 magnitude 7.0 earthquake in Haiti the 4th deadliest in history?
- What have scientists discovered from seismology, satellite observations, and field investigations?
- The Chilean
Heavily damaged home in Banda Aceh, Sumatra from the 2004 tsunami
A severely damaged home, or a portion of one, sits atop debris in Banda Aceh on the island of Sumatra. Damage was caused by a massive, highly destructive tsunami, triggered by a magnitude 9.1 earthquake just offshore of Sumatra, on December 26, 2004.
Epicenter of 2011 Tohoku earthquake in relation to Hawaiian Islands
Map of the 11 March 2011 Tohoku earthquake epicenter in relation to the Northwestern and main Hawaiian Islands
USGS Damage from the magnitude 9.2 earthquake in Alaska
Damage from the magnitude 9.2 earthquake in Alaska on March 27, 1964.
Destruction in Downtown Concepcion, Chile
A masonry building in the downtown part of Concepcion, Chile partially collapsed as a result of the M 8.8 earthquake on Feb. 27, 2010. Most modern buildings in Concepcion were undamaged during the earthquake due to the city's adoption of adequate building standards. However, many masonry buildings such as this one were heavily damaged.