PLANETARY TREMORS: Strong 6.2 Magnitude Earthquake Strikes Off The Coast Of Guatemala - USGS! [MAPS + TECTONIC SUMMARY]

USGS earthquake location.

April 15, 2016 - GUATEMALA - A magnitude-6.2 earthquake has struck an area off the Pacific coast of Guatemala.

There are no immediate reports of damages or injuries.

The U.S. Geological Survey says the quake occurred Friday just after 8 a.m. local time (1400 GMT).

USGS shakemap intensity.

It was centered about 135 miles (219 kilometers) southwest of Guatemala City.

The head of Mexico's civil defense agency says the quake was also felt lightly in the state of Chiapas, which borders Guatemala.

Seismotectonics of the Caribbean Region and Vicinity

Extensive diversity and complexity of tectonic regimes characterizes the perimeter of the Caribbean plate, involving no fewer than four major plates (North America, South America, Nazca, and Cocos). Inclined zones of deep earthquakes (Wadati-Benioff zones), ocean trenches, and arcs of volcanoes clearly indicate subduction of oceanic lithosphere along the Central American and Atlantic Ocean margins of the Caribbean plate, while crustal seismicity in Guatemala, northern Venezuela, and the Cayman Ridge and Cayman Trench indicate transform fault and pull-apart basin tectonics.

Along the northern margin of the Caribbean plate, the North America plate moves westwards with respect to the Caribbean plate at a velocity of approximately 20 mm/yr. Motion is accommodated along several major transform faults that extend eastward from Isla de Roatan to Haiti, including the Swan Island Fault and the Oriente Fault. These faults represent the southern and northern boundaries of the Cayman Trench. Further east, from the Dominican Republic to the Island of Barbuda, relative motion between the North America plate and the Caribbean plate becomes increasingly complex and is partially accommodated by nearly arc-parallel subduction of the North America plate beneath the Caribbean plate. This results in the formation of the deep Puerto Rico Trench and a zone of intermediate focus earthquakes (70-300 km depth) within the subducted slab. Although the Puerto Rico subduction zone is thought to be capable of generating a megathrust earthquake, there have been no such events in the past century. The last probable interplate (thrust fault) event here occurred on May 2, 1787 and was widely felt throughout the island with documented destruction across the entire northern coast, including Arecibo and San Juan. Since 1900, the two largest earthquakes to occur in this region were the August 4, 1946 M8.0 Samana earthquake in northeastern Hispaniola and the July 29, 1943 M7.6 Mona Passage earthquake, both of which were shallow thrust fault earthquakes. A significant portion of the motion between the North America plate and the Caribbean plate in this region is accommodated by a series of left-lateral strike-slip faults that bisect the island of Hispaniola, notably the Septentrional Fault in the north and the Enriquillo-Plantain Garden Fault in the south. Activity adjacent to the Enriquillo-Plantain Garden Fault system is best documented by the devastating January 12, 2010 M7.0 Haiti strike-slip earthquake, its associated aftershocks and a comparable earthquake in 1770.

USGS plate tectonics for the region.

Moving east and south, the plate boundary curves around Puerto Rico and the northern Lesser Antilles where the plate motion vector of the Caribbean plate relative to the North and South America plates is less oblique, resulting in active island-arc tectonics. Here, the North and South America plates subduct towards the west beneath the Caribbean plate along the Lesser Antilles Trench at rates of approximately 20 mm/yr. As a result of this subduction, there exists both intermediate focus earthquakes within the subducted plates and a chain of active volcanoes along the island arc. Although the Lesser Antilles is considered one of the most seismically active regions in the Caribbean, few of these events have been greater than M7.0 over the past century. The island of Guadeloupe was the site of one of the largest megathrust earthquakes to occur in this region on February 8, 1843, with a suggested magnitude greater than 8.0. The largest recent intermediate-depth earthquake to occur along the Lesser Antilles arc was the November 29, 2007 M7.4 Martinique earthquake northwest of Fort-De-France.

The southern Caribbean plate boundary with the South America plate strikes east-west across Trinidad and western Venezuela at a relative rate of approximately 20 mm/yr. This boundary is characterized by major transform faults, including the Central Range Fault and the Boconó-San Sebastian-El Pilar Faults, and shallow seismicity. Since 1900, the largest earthquakes to occur in this region were the October 29, 1900 M7.7 Caracas earthquake, and the July 29, 1967 M6.5 earthquake near this same region. Further to the west, a broad zone of compressive deformation trends southwestward across western Venezuela and central Colombia. The plate boundary is not well defined across northwestern South America, but deformation transitions from being dominated by Caribbean/South America convergence in the east to Nazca/South America convergence in the west. The transition zone between subduction on the eastern and western margins of the Caribbean plate is characterized by diffuse seismicity involving low- to intermediate-magnitude (Magnitude less than 6.0) earthquakes of shallow to intermediate depth.

The plate boundary offshore of Colombia is also characterized by convergence, where the Nazca plate subducts beneath South America towards the east at a rate of approximately 65 mm/yr. The January 31, 1906 M8.5 earthquake occurred on the shallowly dipping megathrust interface of this plate boundary segment. Along the western coast of Central America, the Cocos plate subducts towards the east beneath the Caribbean plate at the Middle America Trench. Convergence rates vary between 72-81 mm/yr, decreasing towards the north. This subduction results in relatively high rates of seismicity and a chain of numerous active volcanoes; intermediate-focus earthquakes occur within the subducted Cocos plate to depths of nearly 300 km. Since 1900, there have been many moderately sized intermediate-depth earthquakes in this region, including the September 7, 1915 M7.4 El Salvador and the October 5, 1950 M7.8 Costa Rica events.

The boundary between the Cocos and Nazca plates is characterized by a series of north-south trending transform faults and east-west trending spreading centers. The largest and most seismically active of these transform boundaries is the Panama Fracture Zone. The Panama Fracture Zone terminates in the south at the Galapagos rift zone and in the north at the Middle America trench, where it forms part of the Cocos-Nazca-Caribbean triple junction. Earthquakes along the Panama Fracture Zone are generally shallow, low- to intermediate in magnitude (Magnitude less than 7.2) and are characteristically right-lateral strike-slip faulting earthquakes. Since 1900, the largest earthquake to occur along the Panama Fracture Zone was the July 26, 1962 M7.2 earthquake.

References for the Panama Fracture Zone:
Molnar, P., and Sykes, L. R., 1969, Tectonics of the Caribbean and Middle America Regions from Focal Mechanisms and Seismicity: Geological Society of America Bulletin, v. 80, p. 1639-1684.

- New Zealand Herald | USGS.

DISASTER IMPACT: Quake Death Toll Climbs After Additional Bodies Discovered in Guatemala - 44 Dead; 9,414 Houses Damaged; Thousands Displaced; State of Emergency in 8 Provinces!

November 4, 2012 - GUATEMALA - Guatemalan emergency agencies recovered two bodies that had been buried in rubble since the powerful earthquake that struck the country last week, bringing the official death toll from the disaster to 44, authorities said Tuesday. 

The latest victims were found in two communities in San Marcos province, the region most affected by the magnitude-7.2 temblor that struck the Central American nation last Wednesday.  Participating in the recovery efforts are dozens of soldiers and firefighters as well as residents of the San Marcos communities. 

Besides the 44 fatalities, the quake left 9,414 houses damaged and forced thousands of people into temporary shelters.  Authorities have still not tabulated the economic losses from the earthquake but President Otto Perez - who is visiting the affected areas - said on Tuesday that an estimate could be in hand by next Friday.  The government decreed a state of emergency in eight of the country’s 22 provinces to facilitate the sending of aid to the affected zones and the process of reconstruction.  Last week’s earthquake was the strongest to hit Guatemala since the Feb. 4, 1976, magnitude-7.5 temblor that claimed the lives of more than 25,000 people and caused millions of dollars in damage. - Hispanically Speaking News.

PLANETARY TREMORS: Strong 6.2 Magnitude Quake Jolts Guatemala's Western Coast!

November 11, 2012 - GUATEMALA - An earthquake measuring 6.2 on the Richter scale jolted offshore Guatemala on Sunday, the U.S. Geological Survey said. This comes against the background of the powerful magnitude 7.5 tremor that struck off the Pacific Coast of Guatemala on Wednesday, killing at least 52 people and shaking buildings as far away as Mexico.

Striking about 18 miles (30 kilometers) below sea level, the tremor was centered about 15 miles west-southwest of Champerico, Guatemala, and 110 miles from the capital, Guatemala City. The quake was not far from southern Mexico, with the USGS reporting it was 24 miles south-southeast of the border community of Suchiate, Mexico. The Pacific Tsunami Warning Center said that "based on all available data, a destructive Pacific-wide tsunami is not expected." - CNN.

Seismotectonics of the Caribbean Region and Vicinity.
Extensive diversity and complexity of tectonic regimes characterizes the perimeter of the Caribbean plate, involving no fewer than four major plates (North America, South America, Nazca, and Cocos). Inclined zones of deep earthquakes (Wadati-Benioff zones), ocean trenches, and arcs of volcanoes clearly indicate subduction of oceanic lithosphere along the Central American and Atlantic Ocean margins of the Caribbean plate, while crustal seismicity in Guatemala, northern Venezuela, and the Cayman Ridge and Cayman Trench indicate transform fault and pull-apart basin tectonics. - USGS.

MAJOR DISASTER IMPACT: Guatemala Death Toll Rises - 52 People Dead and Hundreds Missing, Amid Rubble, Landslides and Devastation!

November 8, 2012 - GUATEMALA - At least 52 dead, and dozens still missing after Guatemala's biggest earthquake in more than three decades.  The 7.4 magnitude earthquake hit off the country's Pacific coast on Wednesday, leaving many villagers near the Mexican border trapped under rubble, as homes and cars were crushed.  Subsequent landslides have blocked roads, making both evacuation and rescue efforts more difficult. 

Guatemala quake – witnesses reported seeing people buried in some of the 30 houses
that collapsed in the town of San Marcos, near Mexico. Photograph: EPA

"It's very sad to meet people here who are waiting to find their families who are still buried," said President Otto Perez in San Marcos, the mountainous region most affected.  "It's really a tragedy and we will do all we can to help the families that are suffering."  Al Jazeera's Rachel Levin, reporting from San Marcos, said a hill had collapsed the day before on a group of seven people, including a five-year-old child.  "We have seen several collapsed homes, and people there are staying with neighbours. We know that supplies are on their way to the most affected areas," she said. "It has been traumatic, people here are still in a state of shock."  Hitting 42km below the surface, it was the strongest earthquake to strike the Central American nation since 1976.

In San Cristobal Cucho, in San Marcos state, all but one of an 11-member family died, buried under rubble, volunteer fireman Ovidio Fuentes told local radio. Only the 17-year-old son survived.  More than 16,000 emergency rations packs have been distributed by more than 2,000 soldiers mobilised to assist relief efforts. At least 73,000 people remain without electricity.  The funerals of all those killed in the impoverished region will be paid for by the government, said Perez. But despite overtures made by officials, some in the devastated area requested improvements be made to facilities there.  "We ask the president to improve conditions at the hospital," said Ingrid Lopez, whose 72-year-old aunt had her legs crushed by a falling wall. "There isn't enough staff."  Office workers evacuated their buildings in Guatemala City, 160km from the quake's epicentre, but soon returned to work.  "It was really big. I felt quite nauseous," said 32-year-old secretary Vanessa Castillo.  Building janitor Jorge Gamboa said: "I was in the bathroom. When I came out the office was empty and I thought, what's happening? They didn't even say goodbye."  The state capital of San Marcos was among the worst-hit cities. Many of the colourful adobe buildings in the 10-square-mile centre of San Marcos were either cracked or reduced to rubble, including the police station and the courthouse. The earthquake left a large gash in one of the streets, and hundreds of frightened villagers stood in the open, refusing to go back inside.  More than 300 people, including firefighters, policemen and villagers, tried to dig through a half ton of sand at a quarry in the commercial centre in a desperate attempt to rescue seven people believed buried alive.  Damage to San Marcos' prison has forced authorities to transfer 101 inmates to another jail.  "We'd rather stay here and reconstruct the jail than be displaced," said inmate Benjamin Tomas Gomez. "That will be hard for our families,''  The quake was felt in El Salvador and more than 1,200km away in Mexico City, where some people also fled offices and homes. - Al Jazeera.

WATCH: Dozens killed in Guatemala earthquake.

DISASTER IMPACT: Deadly Quake - Powerful Tremor Off Guatemala Kills 18, Over 100 Missing, Landslides Block Roadways, and 40 Houses Severely Damaged! UPDATE: Guatemalan President - 39 Dead in 7.4 Magnitude Quake!

November 7, 2012 - GUATEMALA CITY, GUATEMALA - A strong earthquake off the coast of Guatemala shook buildings in the capital and killed at least 18 people On Wednesday, trapping others under rubble and triggering evacuations as far away as Mexico City. 

The 7.4 magnitude quake hit at 10:35 a.m. local time (11:35 EDT). A local fire chief said the dead were buried under rubble in two different Guatemalan towns in the mountainous region near the Mexican border.  Landslides were blocking roads in some areas, authorities said, and about 40 houses were severely damaged.  It was the strongest earthquake to hit Guatemala since a 7.5 magnitude quake in 1976 that claimed more than 20,000 lives.  President Otto Perez said that as many as 100 people were unaccounted for, based on reports from relatives.  "These are preliminary figures and we don't have them confirmed," Perez said in Guatemala City. "Our priority is to focus on lives, rescuing people and treating the wounded."  He said there had been five aftershocks. Local fire chief Cecilio Chacaj said the bodies of the 18 dead had been pulled from rubble in the towns of San Marcos and Quetzaltenango. 

The quake struck off Guatemala's Pacific coast, 15 miles south of Champerico and 101 miles west-southwest of the capital, the U.S. Geological Survey said.  Evacuations in Guatemala City filled the streets with office workers calling friends and relatives on their cell phones, but people soon returned to work.  "It was really big; I felt quite nauseous," said secretary Vanessa Castillo, 32, who was evacuated from her 10th floor office in Guatemala City.  Building janitor Jorge Gamboa said: "I was in the bathroom. When I came out the office was empty and I thought, what's happening? They didn't even say goodbye."  The epicenter was 26 miles below the surface, according to the USGS, which initially reported the quake as magnitude 7.5.  The quake was also felt in El Salvador and more than 765 miles away in Mexico City, where some people also fled offices and homes. Mayor Marcelo Ebrard said the quake was felt strongly in a large part of the city of 20 million people.  The Pacific Tsunami Warning Center said a very small tsunami was registered on Guatemala's coast, adding there was a risk of localized damage within a 62 mile radius. - Reuters.

Here are several images of the damage done in Guatemala:

UPDATE:  Guatemalan President: 39 Dead in 7.4 Magnitude Quake!

A 7.4-magnitude earthquake struck off the Pacific coast of Guatemala Wednesday morning, killing 39 people according to preliminary reports from the country's president. President Otto Perez Molina told a news conference earlier in the day that not all deaths had been confirmed, but others reported of people buried in some of the 30 houses that collapsed in the town of San Marcos near the northwestern border with Mexico, where most of the damage was reported. Ovidio Perez, spokesman for the fire department in San Cristobal Cochu in the state of San Marcos, told the radio station Emisoras Unidas that the 10, including a 4-year old, were buried. At least a dozen were reported injured in the same area. The magnitude-7.4 quake, about 20 miles deep, was centered about 15 miles off the coastal town of Champerico and about 100 miles southwest of Guatemala City, shaking buildings as far away as Mexico City and El Salvador. Survivors by radio and social media talked of widespread landslides and people trapped. But the accounts of deaths and people trapped were difficult to independently confirm as communication and roads were cut off to the area believed most affected, the mountainous state of San Marcos on the northwest border with Mexico.  - CBS News.

PLANETARY TREMORS: Powerful Magnitude 7.5 Quake Strikes Off the Coast of Guatemala - Possibility of a Local Tsunami!

November 7, 2012 - GUATEMALA - A magnitude-7.5 earthquake has struck off the Pacific Coast of Guatemala, the USGS reports, shaking buildings in nearby cities including Mexico City, Guatemala City and San Salvador.

Population Exposure: Overall, the population in this region resides in structures that are vulnerable to earthquake shaking, though some resistant structures exist. The predominant vulnerable building types are mud wall and concrete/cinder block masonry construction. Recent earthquakes in this area have caused secondary hazards such as tsunamis, landslides, and fires that might have contributed to losses - USGS.

The U.S. Pacific Tsunami Warning Center said there was a possibility of a local tsunami, but issued no warning for a larger region. The earthquake was about 20 miles deep and was centered 28 miles off the city of Champerico.

A reporter in the town of San Marcos, about 80 miles north of the epicenter, told local radio station Emisoras Unidas that houses had collapsed onto residents and smashed televisions and other appliances had been scattered into the streets.

The local fire department said on its Twitter account that a school had collapsed and eight injured people had been taken to a nearby hospital. The mayor of Mexico City said no serious damage or injuries had been reported in the city, although many people had fled their offices and homes during the quake. - FOX News.

Seismotectonics of the Caribbean Region and Vicinity.
Extensive diversity and complexity of tectonic regimes characterizes the perimeter of the Caribbean plate, involving no fewer than four major plates (North America, South America, Nazca, and Cocos). Inclined zones of deep earthquakes (Wadati-Benioff zones), ocean trenches, and arcs of volcanoes clearly indicate subduction of oceanic lithosphere along the Central American and Atlantic Ocean margins of the Caribbean plate, while crustal seismicity in Guatemala, northern Venezuela, and the Cayman Ridge and Cayman Trench indicate transform fault and pull-apart basin tectonics.

Along the northern margin of the Caribbean plate, the North America plate moves westwards with respect to the Caribbean plate at a velocity of approximately 20 mm/yr. Motion is accommodated along several major transform faults that extend eastward from Isla de Roatan to Haiti, including the Swan Island Fault and the Oriente Fault. These faults represent the southern and northern boundaries of the Cayman Trench. Further east, from the Dominican Republic to the Island of Barbuda, relative motion between the North America plate and the Caribbean plate becomes increasingly complex and is partially accommodated by nearly arc-parallel subduction of the North America plate beneath the Caribbean plate. This results in the formation of the deep Puerto Rico Trench and a zone of intermediate focus earthquakes (70-300 km depth) within the subducted slab. Although the Puerto Rico subduction zone is thought to be capable of generating a megathrust earthquake, there have been no such events in the past century. The last probable interplate (thrust fault) event here occurred on May 2, 1787 and was widely felt throughout the island with documented destruction across the entire northern coast, including Arecibo and San Juan. Since 1900, the two largest earthquakes to occur in this region were the August 4, 1946 M8.0 Samana earthquake in northeastern Hispaniola and the July 29, 1943 M7.6 Mona Passage earthquake, both of which were shallow thrust fault earthquakes. A significant portion of the motion between the North America plate and the Caribbean plate in this region is accommodated by a series of left-lateral strike-slip faults that bisect the island of Hispaniola, notably the Septentrional Fault in the north and the Enriquillo-Plantain Garden Fault in the south. Activity adjacent to the Enriquillo-Plantain Garden Fault system is best documented by the devastating January 12, 2010 M7.0 Haiti strike-slip earthquake, its associated aftershocks and a comparable earthquake in 1770. - USGS.