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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.
Why are we having so many earthquakes? Has naturally occurring earthquake activity been increasing? Does this mean a big one is going to hit? OR We haven't had any earthquakes in a long time; does this mean that the pressure is building up for a big one?
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.
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.
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.
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.
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.
Southern California is not likely to experience a "huge earthquake,"according to two scientists with the U.S. Geological Survey.
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.
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.
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
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
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.
Map of the 11 March 2011 Tohoku earthquake epicenter in relation to the Northwestern and main Hawaiian Islands
Damage from the magnitude 9.2 earthquake in Alaska on March 27, 1964.
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.