Seismicity of the Chilean coast
Encyclopedia
Seismicity of the Chilean coast identifies and describes the seismic activity of an area of Chile
. Seismicity refers to the frequency, type and size of earthquakes experienced over a period of time. The Chilean coast is on the southern part of South America, which is near a Pacific Ocean subduction zone.
Major earthquakes in Chile occur in a small number of source areas. Those that affect coastal regions are aligned offshore from Concepción to the south. The major epicenters produce a predictable pattern of seismic and tsunami effects.
Significant events that devastated coastal communities in the 20th and 21st centuries include:
The seismicity of the Chilean coast and the top six quakes ever recorded appear to be clustered in two time periods: a 12-year span between 1952 and 1964 and a 7-year span between the 2004 and 2011; however, this is understood as a statistical anomaly
The phenonmenon comparably large quakes that happen on the same or neighbouring faults within months of each other can be explained by a sound geological mechanism; but this does not fully demonstrate a relationship between events separated by longer periods and greater distances
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...
. Seismicity refers to the frequency, type and size of earthquakes experienced over a period of time. The Chilean coast is on the southern part of South America, which is near a Pacific Ocean subduction zone.
Major earthquakes in Chile occur in a small number of source areas. Those that affect coastal regions are aligned offshore from Concepción to the south. The major epicenters produce a predictable pattern of seismic and tsunami effects.
History
The first systematic seismology of Chile began after an earthquake and fire devastated Valparaiso in 1906.Significant events that devastated coastal communities in the 20th and 21st centuries include:
- 1906 Valparaiso earthquake1906 Valparaíso earthquakeThe 1906 Valparaíso earthquake was a strong earthquake that hit Valparaíso, Chile, on August 16, 1906 at 19:55 local time. Its epicenter was offshore from the Valparaíso Region, and its intensity was estimated at magnitude 8.2 MW....
. The 8.8 Chilean quake in August was preceded by the Ecuador-Colombia quake1906 Ecuador-Colombia earthquakeThe 1906 Ecuador-Colombia earthquake occurred at 15:36 UTC on January 31, off the coast of Ecuador, near Esmeraldas. The earthquake had a magnitude of 8.8 and triggered a destructive tsunami that caused at least 500 casualties on the coast of Colombia....
(8.8 magnitude) in January and the San Francisco quake1906 San Francisco earthquakeThe San Francisco earthquake of 1906 was a major earthquake that struck San Francisco, California, and the coast of Northern California at 5:12 a.m. on Wednesday, April 18, 1906. The most widely accepted estimate for the magnitude of the earthquake is a moment magnitude of 7.9; however, other...
(7.9 magnitude) in April. - 1960 Valdivia earthquake. The 9.5-magnitude quake in Chile (largest in modern history) was comparable in scale to earthquakes in Alaska (2nd largest) and the Kamchatka Peninsula (5th largest).
- 2010 Chile earthquake2010 Chile earthquakeThe 2010 Chile earthquake occurred off the coast of central Chile on Saturday, 27 February 2010, at 03:34 local time , having a magnitude of 8.8 on the moment magnitude scale, with intense shaking lasting for about three minutes. It ranks as the sixth largest earthquake ever to be recorded by a...
. The 8.8-magnitude quake in Chile (6th largest) was comparable in scale to undersea seismic events near Indonesia in 2004 (3rd largest) and near Japan in 20112011 Tōhoku earthquake and tsunamiThe 2011 earthquake off the Pacific coast of Tohoku, also known as the 2011 Tohoku earthquake, or the Great East Japan Earthquake, was a magnitude 9.0 undersea megathrust earthquake off the coast of Japan that occurred at 14:46 JST on Friday, 11 March 2011, with the epicenter approximately east...
(4th largest).
The seismicity of the Chilean coast and the top six quakes ever recorded appear to be clustered in two time periods: a 12-year span between 1952 and 1964 and a 7-year span between the 2004 and 2011; however, this is understood as a statistical anomaly
The phenonmenon comparably large quakes that happen on the same or neighbouring faults within months of each other can be explained by a sound geological mechanism; but this does not fully demonstrate a relationship between events separated by longer periods and greater distances