The 2017 Chiapas earthquake struck at 23:49 CDT on 7 September (local time; 04:49 on the 8th UTC) in the

Gulf of Tehuantepec The Gulf of Tehuantepec () is a large body of water on the Pacific coast of the Isthmus of Tehuantepec, southeastern Mexico, at . Many (but not all) Pacific hurricanes form in or near this body of water. A strong, gale-force wind called the T ...

off the southern coast of

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 ...

near the state of

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 ...

, approximately southwest of

Pijijiapan Pijijiapan is a town and municipality in the Mexican state of Chiapas, on the coast of the Pacific Ocean about midway between the border with the state of Oaxaca and the international frontier with Guatemala Guatemala, officially the Repub ...

(alternately, south-southwest of Tres Picos), with a

Mercalli intensity 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 ...

of IX (''Violent''). The

moment magnitude 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 ...

was estimated to be . The earthquake caused all of

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 ...

to tremble, prompting people to evacuate after the early warning system was triggered. It also generated a

tsunami A tsunami ( ; from , ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and underwater explosions (including detonations, ...

with waves above tide level; and tsunami alerts were issued for surrounding areas. Mexico's president called it the strongest earthquake recorded in the country in a century. It was also the second strongest recorded in the country's history, behind the magnitude 8.6 earthquake in 1787, the largest recorded globally in 2017 and the largest earthquake worldwide since the 2015 Illapel earthquake.

Tectonic setting

The

lies above the

convergent boundary A convergent boundary (also known as a destructive boundary) is an area on Earth where two or more lithospheric plates collide. One plate eventually slides beneath the other, a process known as subduction. The subduction zone can be defined by a ...

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 ...

below the North American plate at a rate of 6.4 cm/yr (2.5 in/yr).

Background

On 6 September, several earthquake alarms in Mexico City were mistakenly activated, leading to the evacuation of buildings. The incident prompted a review of the system.

Earthquake

According to the

National Seismological Service The National Seismological Service (, SSN) is a seismological organization in Mexico that studies and records earthquake activity within the country. It is part of the Geophysics Institute at the National Autonomous University of Mexico (UNAM) and ...

(SSN) of Mexico, the

epicenter The epicenter (), epicentre, or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates. Determination The primary purpose of a ...

was located in the Gulf of Tehuantepec, about southeast of

Tonalá, Chiapas Tonalá is a municipality in the state of Chiapas in southern Mexico. As of 2010, the municipality had a total population of 84,594, up from 78,438 as of 2005. It covers an area of 1853km2. As of 2010, the city of Tonalá had a population of 35,3 ...

. The

United States Geological Survey The United States Geological Survey (USGS), founded as the Geological Survey, is an agency of the U.S. Department of the Interior whose work spans the disciplines of biology, geography, geology, and hydrology. The agency was founded on Mar ...

(USGS) reported that the epicenter was about southwest of

, Chiapas. 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 about underground, deeper than usual for a relatively new subduction zone. The SSN reported a measurement of M 8.2, while the USGS also reported a M 8.2 earthquake after correcting an earlier estimate of M 8.0. The earthquake was a result of normal faulting within the Cocos plate with a displacement of up to . The entire thickness of the

lithosphere A lithosphere () is the rigid, outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the lithospheric mantle, the topmost portion of the upper mantle that behaves elastically on time ...

of the Cocos plate ruptured during the earthquake. The earthquake is the most powerful in Mexico to be measured by seismographs. Mexican President

Enrique Peña Nieto Enrique Peña Nieto (; born 20 July 1966), commonly referred to by his initials EPN, is a Mexican former politician and lawyer who was the 64th president of Mexico from 2012 to 2018. A member of the Institutional Revolutionary Party (PRI), he p ...

called the earthquake the "largest in at least a century" and said that it was felt by 50 million people. Geophysicists at the

National Autonomous University of Mexico The National Autonomous University of Mexico (, UNAM) is a public university, public research university in Mexico. It has several campuses in Mexico City, and many others in various locations across Mexico, as well as a presence in nine countri ...

speculated that the earthquake relieved stored pressure in the "Tehuantepec gap", making future earthquakes in the region less likely.

Tsunami

with waves of and higher was generated by the earthquake and was recorded at

Salina Cruz Salina Cruz is a major seaport on the Pacific Ocean, Pacific coast of the List of states of Mexico, Mexican state of Oaxaca. It is the state's fourth-largest city and is the municipal seat of the Municipalities of Oaxaca, municipality of the sa ...

; A tsunami wave of was reported in Chiapas. The

Pacific Tsunami Warning Center The Pacific Tsunami Warning Center (PTWC), located on Ford Island, Hawaii, is one of two tsunami warning centers in the United States, covering Hawaii, Guam, American Samoa and the Northern Mariana Islands in the Pacific, as well as Puerto Ric ...

issued a warning for the entire Pacific coast of

Central America Central America is a subregion of North America. Its political boundaries are defined as bordering Mexico to the north, Colombia to the southeast, the Caribbean to the east, and the Pacific Ocean to the southwest. Central America is usually ...

, also extending south to

Ecuador Ecuador, officially the Republic of Ecuador, is a country in northwestern South America, bordered by Colombia on the north, Peru on the east and south, and the Pacific Ocean on the west. It also includes the Galápagos Province which contain ...

Aftershocks

In the hour following the earthquake, at least 12

aftershock In seismology, an aftershock is a smaller earthquake that follows a larger earthquake, in Epicenter, the same area of the Mainshock, main shock, caused as the displaced Crust (geology), crust adjusts to the effects of the main shock. Large earthq ...

s were recorded by the USGS. As of 00:30 September 14 ( UTC Time), the

(SSN) has recorded at least 1,806 aftershocks, of up to a magnitude of 6.1.

Damage and aftermath

Within Chiapas, an estimated 1.5 million people were affected by the earthquake, with 41,000 homes damaged. Jose Calzada,

Minister of Agriculture An agriculture ministry (also called an agriculture department, agriculture board, agriculture council, or agriculture agency, or ministry of rural development) is a ministry charged with agriculture. The ministry is often headed by a minister f ...

, reported that at least 98 people had died in the earthquake, including 78 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 ...

, 16 in Chiapas and 4 in

Tabasco Tabasco, officially the Free and Sovereign State of Tabasco, is one of the Political divisions of Mexico, 32 Federal Entities of Mexico. It is divided into Municipalities of Tabasco, 17 municipalities and its capital city is Villahermosa. It i ...

. The

Secretariat of the Interior The Secretariat of the Interior (; SEGOB) is the executive department of the Mexican government concerned with the country's domestic affairs, the presenting of the president's bills to Congress, their publication in the ''Official Journal of ...

declared a state of emergency for 122 municipalities in Chiapas, and the

Mexican Army The Mexican Army () is the combined Army, land and Air Force, air branch and is the largest part of the Mexican Armed Forces; it is also known as the National Defense Army. The Army is under the authority of the Secretariat of National Defense o ...

was deployed to aid in disaster relief. Schools were closed on 8 September in 11 states for safety inspections. Damage in

Veracruz Veracruz, formally Veracruz de Ignacio de la Llave, officially the Free and Sovereign State of Veracruz de Ignacio de la Llave, is one of the 31 states which, along with Mexico City, comprise the 32 Political divisions of Mexico, Federal Entit ...

was reported, meanwhile the state is expecting the arrival of Hurricane Katia on 9 September.

Hurricane Max The name Max has been used for six tropical cyclones in the Eastern Pacific Ocean and for one in the Australian region of the Indian Ocean. In the Eastern Pacific: * Tropical Storm Max (1981) – formed in the open ocean * Hurricane Max (1987) – ...

made landfall in

Guerrero Guerrero, officially the Free and Sovereign State of Guerrero, is one of the 32 states that compose the administrative divisions of Mexico, 32 Federal Entities of Mexico. It is divided into Municipalities of Guerrero, 85 municipalities. The stat ...

state on 14 September, near the earthquake-stricken region. Buildings in

Juchitán de Zaragoza Juchitán de Zaragoza (; Spanish name; Isthmus Zapotec: ''Xabizende'' ) is an indigenous town in the southeast of the Mexican state of Oaxaca. It is part of the Juchitán District in the west of the Istmo de Tehuantepec region. With a 2020 cens ...

, closest to the epicenter, were "reduced to rubble" according to reports from the town's mayor. The earthquake also caused buildings to shake and sway in

, while also knocking out electricity for 1.8 million people. There were reports of glass shattered at

Mexico City International Airport Mexico City International Airport (); officially ''Aeropuerto Internacional Benito Juárez'' (Benito Juárez International Airport) is the primary international airport serving Greater Mexico City. It is the List of the busiest airports in Me ...

. A highway bridge under construction near Mexico City's new international airport collapsed due to the shaking. The epicenter was near Mexico's border with Guatemala, where the quake was felt in

Guatemala City Guatemala City (, also known colloquially by the nickname Guate), is the Capital city, national capital and largest city of the Guatemala, Republic of Guatemala. It is also the Municipalities of Guatemala, municipal capital of the Guatemala Depa ...

, and infrastructure damage was reported by CONRED in the nation's south-west. President

Jimmy Morales James Ernesto Morales Cabrera (; born 18 March 1969) is a Guatemalan politician, actor, and comedian who served as the 50th president of Guatemala from 2016 to 2020. Early and personal life Morales was born in Guatemala City to José Everar ...

stated that one Guatemalan was killed. File:Enrique Peña Nieto y Alejandro Murat Hinojosa visitan una zona afectada por el sismo del 7 de septiembre1.jpg, President

inspecting damage to a home in Juchitán, Oaxaca File:Centro de acopio - Terremoto de Chiapas de 2017.jpg, Collection Center for the victims of the earthquake, Mexico City City Hall

Response

On 11 September, Mexico recalled its aid to the United States, offered in the aftermath of

Hurricane Harvey Hurricane Harvey was a devastating tropical cyclone that made landfall in Texas and Louisiana in August 2017, causing catastrophic flooding and more than 100 deaths. It is tied with 2005's Hurricane Katrina as the costliest tropical cy ...

, to focus on earthquake recovery. United States President

Donald Trump Donald John Trump (born June 14, 1946) is an American politician, media personality, and businessman who is the 47th president of the United States. A member of the Republican Party (United States), Republican Party, he served as the 45 ...

called Mexican President

on 14 September, a week after the earthquake, to express his condolences. Three years after the earthquake, Governor Alejandro Murat reported that 60,000 homes have been rebuilt, but that many others still have not been. He reported that sixty health centers have been reconstructed, and in 2020 they plan to rebuild 2,000 schools.

References

External links

M=6.1 Mexican aftershock strongly promoted by M=8.1 Chiapas mainshock
–

Temblor, Inc. Temblor, Inc. is a tech company that provides information about earthquakes and enables users to both see what the seismic hazard is at their home, and learn about precautions to help lessen the risk. The company has released a web app and a mobi ...

* * {{DEFAULTSORT:Chiapas earthquake, 2017 2017 earthquakes 2017 in Guatemala Earthquakes in Guatemala

2017 2017 was designated as the International Year of Sustainable Tourism for Development by the United Nations General Assembly. Events January * January 1 – Istanbul nightclub shooting: A gunman dressed as Santa Claus opens fire at the ...

2017 earthquake 2017 earthquake September 2017 in Mexico 2017 disasters in Mexico