Where do earthquakes occur?
Earthquakes can strike any location at any time, but history shows they occur in the same general patterns year after year, principally in three large zones of the earth:
- The world's greatest earthquake belt, the circum-Pacific seismic belt, is found along the rim of the Pacific Ocean, where about 81 percent of our planet's largest earthquakes occur. It has earned the nickname "Ring of Fire". Why do so many earthquakes originate in this region? The belt exists along boundaries of tectonic plates, where plates of mostly oceanic crust are sinking (or subducting) beneath another plate. Earthquakes in these subduction zones are caused by slip between plates and rupture within plates. Earthquakes in the curcum-Pacific seismic belt include the M9.5 Bio-Bio earthquake in Chile (1960) and the M9.2 Great Alaska Earthquake (1964).
- The Alpide earthquake belt extends from Java to Sumatra through the Himalayas, the Mediterranean, and out into the Atlantic. This belt accounts for about 17 percent of the world's largest earthquakes, including some of the most destructive, such as the 2005 M7.6 shock in Pakistan that killed over 80,000 and the 2004 M9.1 Indonesia earthquake, which generated a tsunami that killed over 230,000 people.
- The third prominent belt follows the submerged mid-Atlantic Ridge. The ridge marks where two tectonic plates are spreading apart (a divergent plate boundary). Most of the mid-Atlantic Ridge is deep underwater and far from human development, but Iceland, which sits directly over the mid-Atlantic Ridge, has experienced earthquakes as large as at least M6.9.
The remaining shocks are scattered in various areas of the world. Earthquakes in these prominent seismic zones are taken for granted, but damaging shocks can occur outside these zones. Examples in the United States include New Madrid, Missouri (1811-1812) and Charleston, South Carolina (1886). However, many years usually elapse between such shocks.
Which states have the smallest number of earthquakes? Is there any place in the world that doesn't have earthquakes?
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.
At least 1783 deaths worldwide resulted from earthquake activity in 2009.
The deadliest earthquake of the year was a magnitude 7.5 event that killed approximately 1117 people in southern Sumatra, Indonesia on Sept. 30, according to the U.S. Geological Survey (USGS) and confirmed by the United Nations Office for Coordination of Humanitarian Affairs (OCHA).
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.
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.
Building in Mexico City after Sept. 19, 2017 earthquake
Ground view of collapsed building and burned area at Beach and Divisadero Streets, Marina District, San Francisco, following the October 17, 1989 Loma Prieta earthquake. At 5:04:15 p.m. (PDT), the magnitude 6.9 (moment magnitude; surface-wave magnitude, 7.1) earthquake severely shook the San Francisco and Monterey Bay regions. The epicenter was located at 37.04° N....
Map of the Pacific Plate boundaries and relative motion, from This Dynamic Planet: World Map of Volcanoes, Earthquakes, Impact Craters, and Plate Tectonics. Third Edition (Published 2006)
By Tom Simkin,1 Robert I. Tilling,2 Peter R. Vogt3,1 Stephen H. Kirby,2 Paul Kimberly,1 and David B....
Villagers in Kerauja, Nepal standing below a large rock slide that resulted in one fatality.
Comparison maps of South America showing 100-year earthquake shaking projections.
This map shows earthquakes above magnitude 4.0 in the eastern United States since 1973, the first year with a complete catalog. There are 184 earthquakes recorded. An earthquake of magnitude 4.0 or greater can cause minor or more significant damage. The circle sizes correspond to earthquake magnitude, ranging from 4.0 to 5.9 (the largest was in the Gulf of Mexico).