.jpg) ShakeMap created by theUSGS | |
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| UTC time | 2022-09-19 18:05:06 |
|---|---|
| ISC event | 624820749 |
| USGS-ANSS | ComCat |
| Local date | 19 September 2022 (2022-09-19) |
| Local time | 13:05:06 |
| Magnitude | Mw 7.6–7.7 |
| Depth | 26.9 km (16.7 mi) |
| Epicenter | 18°35′N103°26′W / 18.59°N 103.43°W /18.59; -103.43[1] |
| Fault | Middle America Trench |
| Type | Thrust |
| Max. intensity | MMI VIII (Severe) |
| Peak acceleration | 0.92g[2] |
| Tsunami | 1.75 m (5 ft 9 in) |
| Aftershocks | 2,000+. Strongest is Mw 6.8.[3] |
| Casualties | 2 dead, 35 injured |
On 19 September 2022, amoment magnitude 7.6–7.7 earthquake struck between theMexican states ofMichoacán andColima at 13:05:06local time.[1][4] The earthquake had a depth of 26.9 km (16.7 mi),[1] resulting in a maximum intensity of VIII (Severe) on theModified Mercalli intensity scale. TheUSGS reported the epicentre was 35 km (22 mi) southwest of the town ofAquila (near the municipality ofCoalcomán).[5] Two people were killed and at least 35 others were injured across several states.[6] A magnitude 6.8 aftershock struck on 22 September, causing three more deaths.[7]
The earthquake coincidentally occurred on the 37th anniversary of the1985 Mexico City earthquake, which killed around 10,000 people, and the fifth anniversary of the2017 Puebla earthquake that struck the state ofPuebla and killed 370 people. A national earthquake drill was being held shortly after midday, less than an hour before the earthquake struck.[8][9][10]
This shallow earthquake occurred in a seismically active zone near the coast of central Mexico. The earthquake occurred near the juncture of threetectonic plates, which are theNorth American plate to the northeast, theRivera plate to the northwest, and theCocos plate to the south. Both the Rivera plate and the Cocos plate are beingsubducted beneath the North American plate. The slower subducting Rivera plate is moving northwest at about 2 centimetres (0.79 in) per year relative to the North American plate and the faster Cocos plate is moving in a similar direction at a rate of about 4.5 centimetres (1.8 in) per year.[11]
Several significant earthquakes have occurred near the recent event. In 1932,a magnitude 8.1 thrust earthquake struck northwest of the 2022 event. On 21 January 2003, amagnitude 7.6 earthquake struck nearby, killing 29 people. On 9 October 1995,a magnitude 8.0 earthquake struck west of the 2022 event, killing 49 people and leaving 1,000 others homeless. The most deadly earthquake in the region also occurred inMichoacán exactly 37 years earlier.This magnitude 8.0 earthquake killed thousands of people, injured about 30,000, and left 100,000 people homeless.[11]
The earthquake occurred as a result ofthrust faulting, on the tectonic boundary between the Cocos plate and the North American plate. This earthquake occurred close to events in1985,1995 and2003. The United States Geological Survey said that earthquakes of this size typicallyrupture over an area measuring 90 km (56 mi) x 40 km (25 mi). A majority of coseismic slip occurred directly beneath land rather than offshore with a maximum displacement at 1.2 m (3 ft 11 in).[4] The subduction interface ruptured at 10–30 km (6.2–18.6 mi) depth and 80 km (50 mi) along the subduction strike. The event produced a maximum slip of 2.9 m (9 ft 6 in). The rupture area overlapped that of a Mw 7.6 earthquake in 1973 with similar rupture size and source duration.[12]
InManzanillo, Colima, a tsunami was observed reaching 0.95 m (3.1 ft).[13][non-primary source needed] The tsunami reached 1.24 m (4 ft 1 in) at a lagoon near Manzanillo, flooding the coastal neighbourhood of Valle de Las Garzas.[14] Near the epicenter, the National Mareographic Service recorded a 1.75 m (5 ft 9 in) tsunami, and at Acapulco, the tsunami measured 0.635 m (2 ft 1.0 in).[2] InZihuatanejo,Guerrero, the tsunami had heights of at least 32 cm (1.05 ft).[15] Sea level fluctuations at Las Salinas lagoon in Zihuatanejo were observed.[16] A tsunami of 12 cm (0.39 ft) was observed inGalapagos Islands, Ecuador.[17]
Aseiche reaching 4 feet (1.2 metres) occurred inDevils Hole atDeath Valley National Park in the United States, about 1,500 miles (2,400 kilometres) away.[18]
Two people were killed and nine were injured in Colima. At least 2,790 homes across 10 municipalities,[19] 20 buildings, two temples and seven medical facilities were damaged. Five bridges and eight roads were destroyed.[20] InManzanillo, one person died when a fence fell on him and some landslides were reported.[21] At Point Plaza Bahia, a mall in the city, a gym partially collapsed, killing one person.[22][23] Communications were disrupted inTecomán andComala, close to the epicentre.[23] Agas tank explosion in Tecomán left four people, including two children, injured.[24]
At least 3,161 homes and 89 schools were affected across Coalcomán, Chinicuila, Coahuayana and Aquila— 800 of which collapsed. The heaviest damage was in Coahuayana, where 1,143 homes were impacted, including 398 which were razed.[25] Damage was reported in 21 hospitals but only two had to be evacuated.[20] Structural damage occurred in eight churches.[26] Several bridges and communication lines were affected. One road collapsed.[20] In Coahuayana, 26 people were injured including one due to a gas explosion.[27]
InGuadalajara, a man's arm was amputated at the elbow during an elevator accident. Debris fell from the temples of San Agustín and La Merced in the city center. AtPuerto Vallarta, ceilings and windows fell from buildings, and some apartment buildings showed cracks between slabs, beams and ground floors.[28] In the town ofTolimán, at least eight houses collapsed.[29]
Inthe state capital, both towers ofTepic Cathedral were heavily damaged, with debris falling from one. In the Villas de Arana subdivision, homes and a hospital were damaged. AtIxtlán del Río, the fence of an elementary school and a financial building were damaged. Stores were damaged and items fell inBahía de Banderas. An abandoned school inCompostela cracked. Two people were injured inSan Blas; one during a motorcycle accident and another due to a fall.[30]
InMexico City, buildings swayed, and at least 97 structures were reported to have sustained slight to moderate damage, some of which were already damaged by previous earthquakes.[31] At least 76 schools in the city were among those damaged. One school was significantly damaged and lessons were suspended.[32]
In addition to the areas identified above, the earthquake was felt strongly in parts ofAguascalientes,Guanajuato,Guerrero,Hidalgo,México,Morelos,Oaxaca,Puebla,Querétaro,Tlaxcala, andZacatecas.[33]
Over 2,000 aftershocks were recorded.[34][35][36] A Mw 5.8 aftershock at 02:17 on 20 September occurred at a depth of 54.5 km (33.9 mi)[37] and was the result of normal faulting along a NW–SE striking, shallow NE dipping plane or a SE–NW striking, steep SW dipping plane.[38]
A magnitude 6.8 aftershock at 01:16 on 22 September at a depth of 20.7 km (12.9 mi)[39] caused power outages in many areas, includingMexico City,[40] where two people were killed; one after falling from a staircase and another due to a heart attack.[41][42] At least 22 buildings were also damaged in the city, one of them seriously.[43] The quake damaged at least one building in the city ofUruapan.[41] InColima, a 5-month-old baby died when a gas explosion occurred.[7] Five others were also injured, including two from said gas explosion.[7][44] In the city ofMetepec, in thestate of Mexico, at least four school buildings were slightly damaged.[45]
This article incorporates text from this source, which is in thepublic domain:"M 7.6 – Colima-Michoacan border region, Mexico". United States Geological Survey.Archived from the original on 19 September 2022. Retrieved20 September 2022. This article incorporates text from this source, which is in thepublic domain:"USGS NEIC: Earthquake Bulletin: COLIMA, MEXICO". United States Geological Survey. Archived fromthe original on 11 May 2008. Retrieved18 May 2008.
