Magnitude 6.5 Earthquake in Guerrero State, Mexico.

The United States Geological Survey recorded a Magnitude 6.5 Earthquake at a depth of 35.0 km, approximately 4 km to the north of the resort of Rancho Viejo in Guerrero State, slightly before 10.00 am local time (slightly before 2.00 pm GMT) on Friday 2 January 2025. This even was felt across much of southern and central Mexico, with at least two people having died, a 50-year-old woman in Guerrero State, and a 60-year-old man in Mexico City. At least 12 further people were injured by the event. 

The approximate location of the 3 January 2026 Guerrero State Earthquake. Contour lines show rates of movement during the quake, the red line is the Middle American Trench. USGS.

Mexico is located on the southernmost part of the North American Plate. To the south, along the Middle American Trench, which lies off the southern coast off Mexico, the Cocos Plate is being subducted under the North American Plate, passing under southern Mexico as it sinks into the Earth. Guatemala is located on the southern part of the Caribbean Plate, close to its boundary with the Cocos Plate, which underlies part of the east Pacific. The Cocos Plate is being pushed northwards by expansion of the crust along the East Pacific Rise, and is subducted beneath the Caribbean Plate along the Middle American Trench. This is not a smooth process, and the plates frequently stick together then break apart as the pressure builds up, causing Earthquakes in the process. 

The position of the Cocos, Nazca and Rivera Plates. MCEER/University at Buffalo.

The Cocos Plate is thought to have formed about 23 million years ago, when the Farallon Plate, an ancient tectonic plate underlying the East Pacific, split in two, forming the Cocos Plate to the north and the Nazca Plate to the south. Then, roughly 10 million years ago, the northwesternmost part of the Cocos Plate split of to form the Rivera Plate, south of Beja California.

In a paper published in the Journal of Geophysical Research, in 2012, a team led by Igor Stubailo of the Department of Earth and Space Sciences at the University of California Los Angeles, published a model of the subduction zone beneath Mexico using data from seismic monitoring stations belonging to the Mesoamerican Seismic Experiment, the Network of Autonomously Recording Seismographs, the USArray, Mapping the Rivera Subduction Zone, and the Mexican Servicio Sismologico Nacional.

The seismic monitoring stations were able to monitor not just Earthquakes in Mexico, but also Earthquakes in other parts of the world, monitoring the rate at which compression waves from these quakes moved through the rocks beneath Mexico, and how the structure of the rocks altered the movement of these waves.

Based upon the results from these monitoring stations, Stubailo et al. came to the conclusion that the Cocos Plate was split into two beneath Mexico, and that the two plates are subducting at different angles, one steep and one shallow. Since the rate at which a plate melts reflects its depth within the Earth, the steeper angled plate melts much closer to the subduction zone than the shallower angled plate, splitting the Trans-Mexican Volcanic Belt into sections above the different segments of the Cocos Plate, and causing it to apparently curve away from the subduction zone.

Top the model of the Cocos Plate beneath Mexico, split into two sections (A & B) subducting at differing angles. (C) Represents the Rivera Plate, subducting at a steeper angle than either section of the Cocos Plate. The Split between the two has been named the Orozco Fracture Zone (OFZ) which is shown extended across the Cocos Plate; in theory this might in future split the Cocos Plate into two segments (though not on any human timescale). Bottom Left, the position of the segments on a map of Mexico. Darker area is the Trans-Mexican Volcanic Belt, orange circles are volcanoes, brown triangles are seismic monitoring stations, yellow stars are major cities. Bottom Right, an alternative model showing the subducting plate twisted but not split. This did not fit the data. Stubailo et al. (2012).

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Tropical Storm Narda kills two after making landfall in Oaxaca.

Tropical Storm Narda made landfall in Oaxaca State, Mexico, on Saturday 28 September 2019, passing over a coastal regions of Guerrero, Michoácan, Colima, Jalisco, and Nayarit, before passing back out to sea over the Gulf of California. The storm caused two fatalities in Ozxaca, a 26-year-old man in San Pedro Mixtepec, and a 17-year-old boy in San Jeronimo, both of whom were swept away by swollen rivers. A landslide in the town of Santa Catarina Juquila, also in Oaxaca, buried two shops, but nobody was hurt in that incident. In Jalisco State the Cuale River overflowed its banks in Puerto Vallarta, causing damage to 248 houses. Flooding was also reported in the city of Mazatlan in Sinaloa State.

 Flooding caused by Tropical Storm Narda in the city of Mazatlan in Sinaloa State. The Mazatlan Post.

Tropical storms are caused by the warming effect of the Sun over tropical seas. As the air warms it expands, causing a drop in air pressure, and rises, causing air from outside the area to rush in to replace it. If this happens over a sufficiently wide area then the inrushing winds will be affected by centrifugal forces caused by the Earth's rotation (the Coriolis effect). This means that winds will be deflected clockwise in the northern hemisphere and anti-clockwise in the southern hemisphere, eventually creating a large, rotating Tropical Storm. They have different names in different parts of the world, with those in the northwest Atlantic and eastern Pacific being referred to as hurricanes.

 The path and strength of Tropical Storm Narda. Thick line indicates the past path of the storm (till 3.00 pm GMT on Tuesday 1 October 2019). Colour indicated the severity of the storm. Tropical Storm Risk.

Despite the obvious danger of winds of this speed, which can physically blow people, and other large objects, away as well as damaging buildings and uprooting trees, the real danger from these storms comes from the flooding they bring. Each drop millibar drop in air-pressure leads to an approximate 1 cm rise in sea level, with big tropical storms capable of causing a storm surge of several meters. This is always accompanied by heavy rainfall, since warm air over the ocean leads to evaporation of sea water, which is then carried with the storm. These combined often lead to catastrophic flooding in areas hit by tropical storms. 

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Second sinkhole opens up in troubled Mexican town.

A second sinkhole has opened up in the town of Pinzán Morado in Guerrero State, Mexico, less than eight months after a similar event forced the abandonment of about 30 homes and two schools in the community. The hole, which opened up this week is about 500 m from the nearest building, and currently measures about 12 m across and 15 m deep, and therefore does not present an immediate threat, but there are concerns that it might behave in a similar way to the previous sinkhole, which opened up in June 2018 and grew to be about 40 m across and 100 m deep.

A sinkhole which opened up in the town of Pinzán Morado in Guerrero State, Mexico, this week. Mexico News Daily. 

Sinkholes are generally caused by water eroding soft limestone or unconsolidated deposits from beneath, causing a hole that works its way upwards and eventually opening spectacularly at the surface. Where there are unconsolidated deposits at the surface they can infill from the sides, apparently swallowing objects at the surface, including people, without trace.

The sinkholes in Pinzán Morado have been linked to former mining activity in the area, particularly the Calentana gold and silver mine, which closed about four years ago after about 25 years of operation, with residents concerned that tunnels in the mine may be collapsing now they are no longer being actively maintained, undermining the ground above and causing sinkholes to appear at the surface.

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Epitomapta simentalae: A new species of Sea Cucumber from Acapulco Bay, Mexico.

Sea Cucumbers (Holothuroidea) are a class of Echinoderms that have become elongated and worm-like, effectively becoming secondarily bilaterally symmetrical. Like all Echinoderms they have a calcareous exoskeleton, but this is greatly reduced, typically only occurring as ossicles within the epidermis. The muscle structure of Sea Cucumbers is instead supported by a layer of modified collegen that can be stiffened or relaxed at will, allowing for a more flexible body than that of other Echinoderms. 

In a paper published in the journal ZooKeys on 15 January 2018, Francisco Alonso Solís-Marín of the Colección Nacional de Equinodermos 'Dra. Ma. Elena Caso Muñoz' at the Universidad Nacional Autónoma de México, Carlos Andrés Conejeros-Vargas of Posgrado en Ciencias del Mar y Limnología at the Universidad Nacional Autónoma de México, Andrea Alejandra Caballero-Ochoa of the Facultad de Ciencias at the Universidad Nacional Autónoma de México, and Julio Adrian Arriaga-Ochoa, also of Posgrado en Ciencias del Mar y Limnología at the Universidad Nacional Autónoma de México, describe a new species of Sea Cucumber from Acapulco Bay on the Pacific Coast of Guerrero State, Mexico.

The new species is placed in the genus Epitomapta, which currently contains two species of small, worm-like Sea Cucumbers from the Atlantic Coast of the United States and the Pacific Coast of Mexico, and given the specific name simentalae, in honour of Delia Rosalba Simental Crespo, for her contributions to the study and conservation of Echinoderms on the coasts of Mexico. The species is described from 127 specimens collected from well aerated sandy sediments at depths of between four and ten meters. These specimens are pink to light purple in colour and less than 2 cm long, with smooth skin and twelve tentacles, each with two or three pairs of digits and a terminal digit, plus up to six sensory cups.

Epitomapta simentalae. Lateral view of preserved specimen. Solís-Marín et al. (2019).

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Striking miners killed in clash with paramilitary group in Guerro State, Mexico.

Two miners have been killed in a clash with a paramilitary group during a protest near Real de Limón in Guerro State, Mexico. The two men  were taking part in a protest in which miners at the El Limón-Guajes Gold Mine on Saturday 18 November 2017, when they were attacked by members of the Policía Comunitaria de Tonalapa, or Tonalapa Community Police (not an official police organisation). The attackers were reportedly detained briefly by members of the Mexican Army, but were released without charge. Workers at the mine have been on strike since 3 November 2017, demanding improved pay and working conditions, and the right to join a worker-led union, and have been blocking access to the mine site as part of the protest.

The El Limón-Guajes Gold Mine in Guerro State, Mexico. Mining Journal.

The El Limón-Guajes Mine is operated by Canadian mining company Torex Gold. The company had agreed that workers at the site were entitled to join a union following an earlier dispute, but instead enrolled them in the Confederación de Trabajadores de México, an employer-led worker's federation, which provides only limited support for ordinary members, rather than the worker-led National Union of Mine, Metal, Steel and Related Workers of the Mexican Republic, which is allied to the American United Steelworkers, and which the miners wanted to join. The dispute has prompted the Canadian Branch of United Steelworkers to petition Canadian Prime Minister Justin Trudeau to intervene, citing his stated desire to improve worker's rights across the North Amercan Free Trade Agreement nations.

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Magnitude 6.4 Earthquake in Guerrero State, southern Mexico.

The United States Geological Survey recorded a Magnitude 6.4 Earthquake at a depth of 24 km, roughly 15 km to the north of the city of Tecpán de Galeana in Guerrero State, southern Mexico, at about 12.00 noon local time (5.00 pm GMT) on Thursday 8 May 2014. There are no reports of any casualties, though minor damage to buildings was reported in Tecpán and Mexico City. The quake was felt across much of southern Mexico, and tall buildings were evacuated in many municipalities temporarily as a precaution.

Minor Damage to a building in Mexico City following the 8 May 2014 Mexican Earthquake. Yuri Cortez/AFP/Getty Images.

Southern Mexico is located on the southernmost part of the North American Plate. To the south, along the Middle American Trench, which lies off the southern coast off Mexico, the Cocos Plate is being subducted under the North American Plate, passing under southern Mexico as it sinks into the Earth. This is not a smooth process, and the plates frequently stick together then break apart as the pressure builds up, causing Earthquakes on the process.

The approximate location of the 8 May 2014 Mexican Earthquake. Google Maps.

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 Magnitude 4.1 Earthquake in Oaxaca State, southern Mexico.

The United States Geological Survey recorded a Magnitude 4.1 Earthquake at a depth of 10 km...

 Magnitude 4.7 Earthquake in Guerrero State, southwest Mexico.

A Magnitude 4.7 Earthquake at a depth of 16.1 km occurred in Guerrero State, southwest Mexico, 15 km...

 Understanding the subduction zone beneath Mexico.

The Middle American Trench, in which the Cocos Plate is subducted beneath the North American Plate, runs parallel to the south coast of Mexico. Like many subduction zones, this feeds a chain of volcanoes...

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58 feared dead following Mexican landslide.

58 people are feared to have died after a landslide hit the coffee-growing village of La Pintada in Guerrero State, southern Mexico, in the aftermath of Tropical Storm Manuel, on Monday 16 September 2013. The landslide passed through the middle of the village, which normally has a population of about 600 but which has now been largely evacuated, destroying a church and an unknown number of homes. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. 

The approximate location of the 16 September 2013 La Pintada landslide. Google Maps.

Much of Mexico has suffered from flooding this week, and the country has suffered a series of landslides, after two major storms converged on the nation at the same time; Tropical Storm Manuel from the west and Hurricane Ingrid from the west. These storms have also contributed to flooding across much of the southern US, most notably in Colorado. The death toll in Mexico currently stands at around 80, but is likely to rise as rescue and reconstruction efforts proceed.

Tropical storms are caused by solar energy heating the air above the oceans, which causes the air to rise leading to an inrush of air. If this happens over a large enough area the inrushing air will start to circulate, as the rotation of the Earth causes the winds closer to the equator to move eastwards compared to those further away (the Coriolis Effect). This leads to tropical storms rotating clockwise in the southern hemisphere and anticlockwise in the northern hemisphere.These storms tend to grow in strength as they move across the ocean and lose it as they pass over land (this is not completely true: many tropical storms peter out without reaching land due to wider atmospheric patterns), since the land tends to absorb solar energy while the sea reflects it.

The low pressure above tropical storms causes water to rise there by ~1 cm for every millibar drop in pressure, leading to a storm surge that can overwhelm low-lying coastal areas, while at the same time the heat leads to high levels of evaporation from the sea - and subsequently high levels of rainfall. This can cause additional flooding on land, as well as landslides.

See also Landslide kills twelve bus passengers as Hurricane Ingrid makes landfall in Veracruz State, Mexico, Five confirmed dead in Colorado flooding, and over 600 still missing, At least eighteen deaths as Tropical Storm Manuel hits Guerro State in southern Mexico, At least one dead as Tropical Storm Juliette crosses the tip of Baja California and Thirteen dead after Tropical Storm Ferdinand hits Veracruz State in southeast Mexico.

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At least eighteen deaths as Tropical Storm Manuel hits Guerro State in southern Mexico.

At least eighteen people have died as Tropical Storm Manuel hit the Pacific coast of Guerro State in Mexico on Sunday 15 September. In Acapulco a family of six were wiped out when their house was his by a landslide, three people were swept away by floods and a tenth person was crushed by a collapsing wall. Elsewhere in Guerro State a further six people died when the vehicle they were traveling skidded in wet conditions and two more people were killed in separate landslides. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. 

An overturned car on top of landslide debris in Acapulco, Mexico, on Sunday 15 September 2013, following Tropical Strom Manuel. AP.

Tropical storms are caused by solar energy heating the air above the oceans, which causes the air to rise leading to an inrush of air. If this happens over a large enough area the inrushing air will start to circulate, as the rotation of the Earth causes the winds closer to the equator to move eastwards compared to those further away (the Coriolis Effect). This leads to tropical storms rotating clockwise in the southern hemisphere and anticlockwise in the northern hemisphere.These storms tend to grow in strength as they move across the ocean and lose it as they pass over land (this is not completely true: many tropical storms peter out without reaching land due to wider atmospheric patterns), since the land tends to absorb solar energy while the sea reflects it.

The low pressure above tropical storms causes water to rise there by ~1 cm for every millibar drop in pressure, leading to a storm surge that can overwhelm low-lying coastal areas, while at the same time the heat leads to high levels of evaporation from the sea - and subsequently high levels of rainfall. This can cause additional flooding on land, as well as landslides. Tropical Storm Manuel has brought 25-40 cm of rain within 24 hours across much of Guerro State.

See also At least one dead as Tropical Storm Juliette crosses the tip of Baja California, Thirteen dead after Tropical Storm Ferdinand hits Veracruz State in southeast Mexico, Two people killed as Hurricane Barbara makes landfall on Mexican south coast, Texas Tornado kills six and Hurricane Sandy heads towards east coast of America.

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Magnitude 4.7 Earthquake in Guerrero State, southwest Mexico.

A Magnitude 4.7 Earthquake at a depth of 16.1 km occurred in Guerrero State, southwest Mexico, 15 km southeast of the city of Ometepec, slightly before 9.45 pm local time on Sunday 8 September 2013 (slightly before 4.45 am on Monday 9 September, GMT) according to the United States Geological Survey. There are no reports of any damage or injuries arising from this quake, though it may have been felt locally.

The approximate location of the 8 September 2013 Guerrero State Earthquakes. Google Maps.

Southern Mexico is located on the southernmost part of the North American Plate. To the south, along the Middle American Trench, which lies off the southern coast off Mexico, the Cocos Plate is being subducted under the North American Plate, passing under southern Mexico as it sinks into the Earth. This is not a smooth process, and the plates frequently stick together then break apart as the pressure builds up, causing Earthquakes on the process.

See also Magnitude 6.6 Earthquake in southwest Guatemala causes at least one death, Magnitude 6.2 Earthquake in southern Mexico, Fresh eruption on Mount Popocatépetl disrupts flights around Mexico City, Mexico City shaken by Magnitude 5.8 Earthquake and Eruption on Mount Popocatépetl.

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