1960 Concepción earthquakes

The first 1960 Concepción earthquake
1960 Concepción earthquakes is located in South America
1960 Concepción earthquakes
1960 Concepción earthquakes is located in Chile
1960 Concepción earthquakes
UTC time1960-05-21 10:02
ISC event879106
USGS-ANSSComCat
Local date21 May 1960 (21 May 1960)
Local time6:02 AM UTC-4
Magnitude8.1 Mw[1]
8.3 Ms[2][3][4]
Depth25.0 km (15.5 mi)[1]
Epicenter37°49′26″S 73°21′11″W / 37.824°S 73.353°W / -37.824; -73.353[1]
Areas affectedChile
Max. intensityMMI X (Extreme)[5]
Casualties125 dead

The 1960 Concepción earthquakes were a succession of three destructive earthquakes that happened between 21 and 22 May 1960. They formed part of the foreshock sequence for the 1960 Valdivia earthquake, the largest recorded earthquake in history.[6]

The first was on May 21 at 06:02 UTC-4.[3][7] Its epicenter was near Cañete, Bío Bío Region, Chile, and its magnitude was 8.1 [1] or 8.3[2]MW and 7.3[3] or 7.5[4]MS. This earthquake, which lasted 35 seconds, destroyed a third of the buildings in the city of Concepción.[8]

The earthquake effectively interrupted and ended Lota's coal miners march on Concepción where they demanded higher salaries.[9]

First earthquake intensity[5]
21 May at 6:02 UTC earthquake
City MMI Damage
Concepción IX 125 dead. A third of the buildings were destroyed.[8]
Talcahuano IX 65% of buildings were destroyed.
Coronel IX
Lota IX
Lebu X
The second 1960 Concepción earthquake
UTC time1960-05-22 10:30:44
ISC event879127
USGS-ANSSComCat
Local date22 May 1960 (1960-05-22)
Local time06:30 AM UTC-4
Magnitude7.1 Mw[10]
Depth25.0[10] km
EpicenterNahuelbuta National Park
37°46′30″S 73°01′02″W / 37.77500°S 73.01722°W / -37.77500; -73.01722[10]
Areas affectedConcepción, Arauco and Ñuble in Chile
Max. intensityMMI VII (Very strong)[10]

The second happened on May 22 at 06:30 UTC-4.[11] Its epicenter was in the Nahuelbuta National Park, Araucanía Region, Chile, and its magnitude was 7.1 Mw.[10] It was followed by a 6.8 Mw earthquake at 06:32 UTC-4.[12]

The third 1960 Concepción earthquake
UTC time1960-05-22 18:56:02
ISC event879134
USGS-ANSSComCat
Local date22 May 1960 (1960-05-22)
Local time14:56 PM UTC-4
Magnitude7.8[13] Mw 7.8[4] MS
Depth25 km[13]
EpicenterPurén
38°03′39.6″S 73°02′20.4″W / 38.061000°S 73.039000°W / -38.061000; -73.039000[13]
Areas affectedConcepción, Arauco and Ñuble in Chile

The third happened the same day at 14:56 UTC-4. Its epicenter was near Purén, Araucanía Region, Chile and its magnitude was 7.8 MS or 7.8 Mw.[13] This earthquake happened 15 minutes before the 1960 Valdivia earthquake.[4]

See also

References

  1. ^ a b c d "M8.1 – Bio-Bio, Chile 1960-05-21 10:02:54 UTC". United States Geological Survey. Retrieved 1 June 2015.
  2. ^ a b Vigny, C.; Socquet, A.; Peyrat, S.; Ruegg, J.C.; Métois, M.; Madariaga, R.; Morvan, S.; Lancieri, M.; Lacassin, R.; Campos, J.; et al. (2011). "The 2010 Mw 8.8 Maule Megathrust Earthquake of Central Chile, Monitored by GPS". Science. 332 (6036): 1417–21. Bibcode:2011Sci...332.1417V. doi:10.1126/science.1204132. PMID 21527673.
  3. ^ a b c Servicio Sismológico Universidad de Chile, Sismos importantes o destructivos desde 1570 Archived 2012-06-29 at archive.today
  4. ^ a b c d SHOA. "Generalities". Archived from the original on 2011-07-09. Retrieved June 10, 2011. The sequence started with an earthquake magnitude Ms=7.5 at 10:02 GMT on May 21st, followed by another on May 22nd, magnitude Ms=7.8 at 18:55 GMT
  5. ^ a b Jean Pierre Rothe: The seismicity of the earth, 1953–1965. UNESCO, Paris 1969. (Abstract in the United States Geological Survey web site Archived 2011-08-06 at the Wayback Machine)
  6. ^ Barrientos S.E.; Ward S.N. (1990). "The 1960 Chile earthquake: inversion for slip distribution from surface deformation". Geophysical Journal International. 103 (3): 589–598. Bibcode:1990GeoJI.103..589B. doi:10.1111/j.1365-246X.1990.tb05673.x.
  7. ^ Ojeda J.; Ruiz S.; del Campo F.; Carvajal M. (2020). "The 21 May 1960 M w 8.1 Concepción earthquake: A deep megathrust foreshock that started the 1960 central-south Chilean seismic sequence". Seismological Research Letters. 91 (3): 1617–1627. doi:10.1785/0220190143.
  8. ^ a b Rudolph, William E. (1960). "Catastrophe in Chile". Geographical Review. 50 (4): 578–581. Bibcode:1960GeoRv..50..578R. doi:10.2307/212311. JSTOR 212311.
  9. ^ Reyes Herrera, Sonia E.; Rodríguez Torrent, Juan Carlos; Medina Hernández, Patricio (2014). "El sufrimiento colectivo de una ciudad minera en declinación. El caso de Lota, Chile". Horizontes Antropológicos (in Spanish). 20 (42).
  10. ^ a b c d e "M 7.1 – Bio-Bio, Chile". United States Geological Survey. Retrieved 19 November 2016.
  11. ^ "M 7.1 – Bio-Bio, Chile". United States Geological Survey. Retrieved 19 November 2016.
  12. ^ "M 6.8 – Bio-Bio, Chile". United States Geological Survey. Retrieved 19 November 2016.
  13. ^ a b c d "M 7.8 – Araucania, Chile". United States Geological Survey. Retrieved 19 November 2016.