October 11, 2013 - CARIBBEAN - A brief temblor said to be of around 6.2 on the Richter Scale struck around 10.13 pm tonight off Venezuela and was felt in Trinidad, Georgetown and other parts of Guyana.
City residents felt around a three-second tremor which had many asking questions about the source of the earth-shaking.
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| USGS earthquake location. |
The earthquake was said to have occurred 33km N of Gueiria, Venezuela, according to the website www.volcanodiscovery.com. The website featured reactions from Trinidadians, Venezuelans and Guyanese about what they had felt.
Moderate shaking was experienced in many parts of Trinidad, according to the website, and the duration of the temblor closer to the epicentre was between 15 and 20 seconds.
The US Geological Survey is reporting that the earthquake occurred at a depth of 79.4 km. The quake was fifty-three miles west of Port of Spain, Trinidad and Tobago, sixty-two miles west of Port Fortin and sixty-three miles west of Tunapuna as well.
A news item in today’s Trinidad Express follows:
(Trinidad Express) Trinidad was rattled by a magnitude 6.4 earthquake (preliminary data) Friday night, causing fear and unease among citizens concerned that it was intense enough to have caused damage, or trigger a tsunami.
However, there were no immediate reports of damage, and no tsunami warning was issued.
The earthquake was strong enough to cause disruption of the electricity supply, with T&TEC reporting issues at its sub stations in Carenage, Pt. Cumana and Santa Flora.
The Office of Disaster Preparedness and Management issued a statement to advise citizens that it has put all first responder agencies on alert so that immediate assistance can be rendered if any adverse impact occurs. “Citizens are reminded to contact 511 if they have been adversely affected”, the ODPM stated.
According to the University of the West Indies Seismic Research Centre , at 10:10pm local time, an earthquake occurred north of the Paria Peninsula, Trinidad. The event was located at 10.86°N 62.12°W. The magnitude was 6.4 and depth 60km.
Social media immediately lit up, with people sharing their experiences following the shake which lasted for a lengthy period and which occurred during the local government campaign meetings of the United National Congress in Debe, the Movement for Social Justice in Point Fortin and the Independent Liberal Party in Princes Town.
Some reported pictures becoming dislodged from walls, and objects toppling from cupboards and cabinets. Others said they screamed and took cover under door frames. Many said they paused and prayed.
The quake is the latest in a series, the last occurring on Monday 9th September, at 9:54am, west of Trinidad in the Gulf of Paria. The event was located at 10.25°N and 61.75°W. The magnitude was 3.8 and the depth 76km. There were felt reports from St. James and Diego Martin, Trinidad.
On Tuesday 27th August, 2013 at 7:59am local time an earthquake occurred North-west of Trinidad. The event was located at 10.76°N and 61.79°W. The magnitude was 3.9 and the depth 57 km. There were felt reports from Cocorite and Maraval, Trinidad”.
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At 10.45 a.m on August 8,an earthquake occurred north of the Paria Peninsular, which is off Trinidad northwest coast.
“The event was located at 10.72N 62.33W. The magnitude was 3.8 with a depth of 77km. This event has been reported to be felt in Port of Spain Trinidad”, the SRC stated.
At 10:56a.m on August 6, a quake was recorded north of Paria Peninsula.
The SRC gave the location as 10.75°N 62.13°W. The magnitude was 4.1 and depth 54km. No injuries or damage were reported.
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Stabroek News.
A 6.1-magnitude earthquake struck near the coast of Venezuela on Friday evening and was felt in Trinidad and Tobago, according to the United States Geological Survey.
There were reports of moderate shaking across the region, including Trinidad, Guyana, Grenada Venezuela.
The University of the West Indies rated the quake at a magnitude of 6.4, although UWI frequently has readings higher than those of the USGS.
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| USGS earthquake shakemap intensity. |
The tremor’s epicentre was about 33 kilometres north of Gueiria, Venezuela, and about 86 kilometres west-northwest of Port of Spain, according to the United States Geological Survey.
It occurred at around 10:10 PM in Trinidad at a depth of about 79 kilometres, according to the USGS.
It was the strongest earthquake in the Caribbean region in several years.
In a statement, Trinidad’s Office of Disaster Preparedness and Management said there were no reports of damages thus far. There have been reports of issues with the power grid, however. -
Carib Journal.
A tremor rattled Guyana at approximately 10:12 PM (local time) around the same time a quake measuring 6.1 on the Richter Scale shook north-eastern Venezuela.
There were no immediate reports of damage. Persons in Georgetown as well as far away as Corriverton, Berbice, Linden, Bartica, Mahdia and the North West District felt the earth shiver.
Around the same time, the United States Geological Surveys (USGS) reported a 6.0 earthquake at 10:10 PM about 27 kilometers North North East of Gueiria, Venezuela to a depth of 86 kilometers. The location was 10.818°N 62.233°W. -
Guyanese Online.
An earthquake with a magnitude of 6.4 jolted several Caribbean countries, including Trinidad and Tobago and Guyana on Friday night, the Trinidad-based Seismic Unit of the University of the West Indies (UWI) confirmed Saturday.
It said that the quake, which was also felt in Grenada and St Vincent and the Grenadines occurred at 10:10 pm and was located north of the Paria Peninsula in Trinidad.
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| USGS earthquake location. |
The Guyana-based Demerara Waves website said that the tremor was felt as far away as Corriverton, Berbice, Linden, Bartica, Mahdia and the North West District.
There were no immediate reports of damage or death caused by the quake which had a depth of 60 kilometres and was located 10.86 degrees north, 62.12 degrees west.
Media reports in Trinidad made reference to electricity power cuts but no serious damage or injuries. The quake is the most powerful felt in Trinidad and Tobago since 1997 when an earthquake with a magnitude of 6.1 struck the twin island republic causing damage in the sister isle of Tobago. -
Jamaica Observer.
Tectonic Summary - 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.
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| USGS plate tectonics for the region. |
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.
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
Columbia. 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. -
USGS.