The 2018 Oaxaca earthquake occurred on February 16, 2018, at 17:39

local time Local time is the time observed in a specific locality. There is no canonical definition. Originally it was mean solar time, but since the introduction of time zones it is generally the time as determined by the time zone in effect, with daylight s ...

(23:39

UTC Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communica ...

) in the

Sierra Madre del Sur The Sierra Madre del Sur is a mountain range in southern Mexico, extending from southern Michoacán east through Guerrero, to the Isthmus of Tehuantepec in eastern Oaxaca. Geography The Sierra Madre del Sur joins with the Eje Volcánico Transv ...

mountains in

Oaxaca Oaxaca, officially the Free and Sovereign State of Oaxaca, is one of the 32 states that compose the political divisions of Mexico, Federative Entities of the Mexico, United Mexican States. It is divided into municipalities of Oaxaca, 570 munici ...

state in Southern

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

. It had a magnitude of 7.2 on the

moment magnitude scale The moment magnitude scale (MMS; denoted explicitly with or Mwg, and generally implied with use of a single M for magnitude) is a measure of an earthquake's magnitude ("size" or strength) based on its seismic moment. was defined in a 1979 paper ...

and a maximum felt intensity of VII (''Very strong'') on the

Mercalli intensity scale The Modified Mercalli intensity scale (MM, MMI, or MCS) measures the effects of an earthquake at a given location. This is in contrast with the seismic magnitude usually reported for an earthquake. Magnitude scales measure the inherent force or ...

. The

hypocenter A hypocenter or hypocentre (), also called ground zero or surface zero, is the point on the Earth's surface directly below a nuclear explosion, meteor air burst, or other mid-air explosion. In seismology, the hypocenter of an earthquake is its ...

was located at a depth of 24.6 km and approximately 37 km northeast of Pinotepa de Don Luis. There were only two reports of injuries from the earthquake, but later a military helicopter surveying the damage crashed and killed 14 people. There were also 15 people injured.

Tectonic summary

Oaxaca lies on the destructive plate boundary where the Cocos plate is being

subducted Subduction is a geological process in which the oceanic lithosphere and some continental lithosphere is recycled into the Earth's mantle at the convergent boundaries between tectonic plates. Where one tectonic plate converges with a second plat ...

beneath the North American plate. In the region of this earthquake, the Cocos plate moves approximately northeastward at a rate of 60 mm/yr. The earthquake occurred as a result of

thrust fault A thrust fault is a break in the Earth's crust, across which older rocks are pushed above younger rocks. Thrust geometry and nomenclature Reverse faults A thrust fault is a type of reverse fault that has a dip of 45 degrees or less. I ...

ing at a shallow depth. The depth and

focal mechanism The focal mechanism of an earthquake describes the Fault (geology)#Slip.2C heave.2C throw, deformation in the Hypocenter, source region that generates the seismic waves. In the case of a Fault (geology), fault-related event, it refers to the ori ...

solutions of the event are consistent with its occurrence on the subduction zone interface between these plates, approximately 90 km northeast of the

Middle America Trench The Middle America Trench is a major subduction zone, an oceanic trench in the eastern Pacific Ocean off the southwestern coast of Middle America, stretching from central Mexico to Costa Rica. The trench is 1,700 miles (2,750 km) long an ...

. Historically, several significant earthquakes have occurred along the southern coast of Mexico. In 1932, a M 8.4 megathrust earthquake struck in the region of Jalisco, several hundred kilometers to the northwest of the Oaxaca event. On October 9, 1995, a M 8.0 earthquake struck in the

Colima Colima, officially the Free and Sovereign State of Colima, is among the 31 states that make up the 32 Federal Entities of Mexico. It shares its name with its capital and main city, Colima. Colima is a small state of western Mexico on the cen ...

-Jalisco region, resulting in at least 49 fatalities and leaving 1,000 people homeless. The deadliest nearby earthquake occurred on September 19, 1985, in the

Michoacán Michoacán, formally Michoacán de Ocampo, officially the Free and Sovereign State of Michoacán de Ocampo, is one of the 31 states which, together with Mexico City, compose the Political divisions of Mexico, Federal Entities of Mexico. The stat ...

region 500 km to the northwest of the February 16th event. This M 8.0 earthquake resulted in at least 9,500 fatalities, injured about 30,000 people, and left 100,000 people homeless. In 2003, a M 7.6 earthquake in Colima, Mexico, resulted in 29 fatalities, destroyed more than 2,000 homes and left more than 10,000 people homeless. In March 2012, a M 7.4 earthquake 60 km to the northwest of the February 16, 2018, event killed 2 and injured 11 in the Oaxaca region. The hypocenter of the M 8.2 earthquake off the shore of Chiapas in September 2017 was located 440 km southwest of this earthquake. The Chiapas event caused at least 78 fatalities and 250 injuries in Oaxaca, and a further 16 deaths in

Chiapas Chiapas, officially the Free and Sovereign State of Chiapas, is one of the states that make up the Political divisions of Mexico, 32 federal entities of Mexico. It comprises Municipalities of Chiapas, 124 municipalities and its capital and large ...

. Eleven days later, a M 7.1 earthquake struck closer to Mexico City, 230 km northeast of today's earthquake, resulting in over 300 fatalities and significant damage in

Mexico City Mexico City is the capital city, capital and List of cities in Mexico, largest city of Mexico, as well as the List of North American cities by population, most populous city in North America. It is one of the most important cultural and finan ...

and the surrounding region. A second quake, registering 5.9, struck Oaxaca on February 19, 2018, around 12:57 AM local time. The quake, believed to be an aftershock, had an epicenter about 69 miles southwest of Oaxaca City; its impact was registered in Mexico City. No deaths were reported from this quake.

Helicopter crash

Alejandro Murat Hinojosa Alejandro Ismael Murat Hinojosa (born August 4, 1975) is a Mexican politician affiliated with Morena. He was elected Governor of Oaxaca in 2016 as a member of the Institutional Revolutionary Party and took office from December 1, 2016, to Novem ...

, the

Governor of Oaxaca The governor of Oaxaca (officially in Spanish ''Gobernador Constitucional del Estado Libre y Soberano de Oaxaca'', in English ''Constitutional Governor of the Free and Sovereign State of Oaxaca''), heads the executive branch of the Mexican state ...

, was in

Tuxtepec San Juan Bautista Tuxtepec (, "on the hill of rabbits"), or simply referred to as Tuxtepec, is the head of the municipality by the same name and is the second most populous city of the Mexican state of Oaxaca. It is part of the Tuxtepec District of ...

at the time the earthquake struck and immediately left to survey the damage in Pinotepa Nacional with Alfonso Navarrete Prida, who had become the

Secretary of the Interior Secretary of the Interior may refer to: * Secretary of the Interior (Mexico) * Interior Secretary of Pakistan * Secretary of the Interior and Local Government (Philippines) * United States Secretary of the Interior See also

*Interior ministry ...

the month before. The

Sikorsky UH-60M Black Hawk Sikorsky or Sikorski may refer to: * Sikorsky (comics), a Marvel Comics character * Sikorsky (crater), a lunar crater * Sikorsky Aircraft, an American aircraft manufacturer People with the surname * Brian Sikorski (born 1974), Major League Basebal ...

military helicopter in which Murat and Navarrete, along with the state head of civil protection and one other person, were traveling, crashed in

Santiago Jamiltepec Santiago Jamiltepec (Mixtec: Casandoo) is a town, and the seat of surrounding municipality of the same name, in the Mexican state of Oaxaca. It is located in the Jamiltepec District in the west of the Costa Chica Region, 30 km east of Pin ...

while attempting to land nearby when the pilot lost control of the aircraft. The helicopter crashed on two cars that were parked in a field, where a family was spending the night outside after the earthquake. A total of 14 people, all of them on the ground, were killed, and 15 others were injured. All four people on board the helicopter survived unharmed.

References

External links

* {{Aviation accidents and incidents in 2018 2018 earthquakes Earthquakes in Mexico February 2018 in Mexico History of Oaxaca 2018 disasters in Mexico