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Instrumental seismicity
About 200 earthquakes are located in and around Jamaica per year most of which are minor, having m...
Jamaica's Earthquake History

Jamaica’s recorded history is rife with incidences of felt earthquakes. The famous Port Roya...
merchandise in shops
1957 March 1

1993 Jan 13

2005 June 12


Montego Bay, St. James and felt

4 dead; l...
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CARIBBEAN STUDIES Instrumental seismicity in jamaica


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CARIBBEAN STUDIES Instrumental seismicity in jamaica

  1. 1. Instrumental seismicity About 200 earthquakes are located in and around Jamaica per year most of which are minor, having magnitudes less than 4.0. The most seismically active areas are the Blue Mountain block in eastern Jamaica and the Montpelier-Newmarket belt in western Jamaica. Other areas of notable seismicity include the near offshore south-west of Black River on the south coast, and offshore Buff Bay on the north–east coast. Offshore: WFZ - Walton Fault Zone; NJF - North Jamaica Fault; EF - Enriquillo Fault Major land faults: ML - Maryland; DFZ - Duanvale; SCr - Santa Cruz; ST - Spur Tree; SoC - South Coast; RMCR - Rio Minho-Crawle River; WW - Wagwater; BM - Blue Mountain; YPG - Yallahs-Plantain Garden Other Structural features: H - Hanover Block; NCB - North Coast Block; C - Clarendon Block; B - Blue Mountain Block; MNB - Montpelier-Newmarket Belt; WWB - Wagwater Belt (After Jamaica Geological Structure Series Map 92-21, 1992) For a look at a presentation on Jamaican Seismicity, click here. Adobe Acrobat will be reqiured to retrieve this document. Sub-Regional Tectonics Jamaica is associated with the Gonave micro-plate, which is demarcated by the Oriente Fracture Zone (OFZ) to the north, the Walton (WFZ) and Enriquillo Fault Zones (EFZ) to the south and the Cayman Spreading Centre (CSC) to the west. The OFZ, spanning a distance of over 1000 kilometres, from south of Grand Cayman to the north coast of Haiti, is known to be a left-lateral strike-slip fault which means there is a relative westerly drift of Cuba (on the North American Plate) with respect to Jamaica. Jamaica, with parts of Cuba and Hispanola showing relevant plate boundaries - red dots represent past epicentres The Walton and Enrriquillo Faults are also left-lateral strike-slip features that separate the Gonave sliver from the Caribbean Plate to the south. Measurements made using Global Positioning System (GPS) indicate 18 mm/year of lateral strain and 3mm/yr of convergence on the OFZ near south-eastern Cuba, and 8-11 mm/yr on Jamaica. Local Tectonics Jamaica itself is traversed by a number of geological faults that feature Quaternary left-lateral offsets. In eastern Jamaica there is the Plantain Garden fault that runs into the Yallahs, Blue Mountain, Wagwater and Silver Hill faults, which together control the tectonics of the Blue Mountain block. In western Jamaica the topography is influenced by the South Coast, Spur Tree and Montpelier-Newmarket faults that exhibit large downthrows to the south and west, respectively. Earthquakes occurring across the country today predominantly exhibit strikeslip faulting, which mirrors the movements along the OFZ
  2. 2. Jamaica's Earthquake History Jamaica’s recorded history is rife with incidences of felt earthquakes. The famous Port Royal earthquake of June 7, 1692 was perhaps our largest and most damaging natural disaster. Although it was felt island-wide, the most extensive loss of life occurred at Port Royal, where a portion of the town sank into the sea. At least 2,000 persons died as a result of an outbreak of yellow fever, which developed after the quake. (To read more on this 1962 Earthquake, click here.) The Great Kingston Quake of 1907 occurred January 14,of that year. Of the 48,000 people living in Kingston at the time, over 1000 perished, mostly in the fires following the shocks (main and after-shocks). The aftershocks continued for the rest of the year. Some 9,000 people were left homeless throughout the island. Damage (building) for that event was estimated at two million pounds (back then).(To read a news account on this 1907 Earthquake, click here.) The March 1, 1957 event, affected mostly Western Jamaica. The most damages were recorded in the parish of St. James, especially for its infrastructure such as buildings, bridges and roads. This event resulted in three (3) deaths and three associated fires. A full list of damaging earthquakes can be seen here in ourEarthquake Data page. Monitoring for earthquakes in Jamaica began with the weather service in the late 19th century. In the early 20th century the Jesuits Association also established seismograph stations on the island. However, it was not until the early 1960s that the first modern seismograph station was installed at Hope Gardens, Geological Survey Division. In 1963, that station was moved to the Mona campus of the University of the West Indies, from where the growth into the Jamaica Seismograph Network began. In the 1970s, the number of stations increased to three and this enabled details of epicentres and focal depths of earthquakes to be determined. Thus, the database of felt earthquakes extends back to the 17th century, while that for located events is only about 30 years long. Artist's impression of 1692 Earthquake. Illustrated is the liquefaction and ground failure as the earth opens up to swallow the unfortunate residents Pictures of the damaged Parish Church, Westmoreland and a school in St. James taken from The Gleaner, March 1957 Most Damaging Earthquakes in Jamaica Year Date Maximum Intensity (EMS) * Places Affected Observed Damage 1667 - VIII - Landslide 1688 March 1 VII Port Royal Houses and ships damaged 1692 June 7 X Port Royal, Kingston, Vere Plains. Also felt strongly island-wide 3,000 dead; buildings collapsed; liquefaction, subsidence, landslides and water ejected 1771 Sept 3 VII Port Royal, Kingston Damage to structures, felt on boats in port. November 1812 VIII 11 Kingston Several people killed; walls fell, buildings damaged 1824 April 10 Kingston; Spanish Town, St. Loud noise accopmanied shock; some houses Catherine; Old Harbour, Clarendon fell 1839 VII November VII 5 Montego Bay, St.James Government buildings declared unsafe due to damage 1907 Jan 14 IX Kingston, Port Royal 1,000 dead; fire over 56 acres; most buildings collapsed; water mains broken; landslides and slumps; localized tsunami; statues rotated; near total destruction of damage - est. 2 million pounds sterling in damage 1914 August 3 VII Eastern Jamaica Buildings cracked, doors and windows out of plumb; clocks stopped; stocks in drug stores broken 1943 July 15 VII St. Elizabeth Landslides; many homeless; breakages of
  3. 3. merchandise in shops 1957 March 1 1993 Jan 13 2005 June 12 VIII Montego Bay, St. James and felt island-wide 4 dead; ladnslides; bridges damaged; rotation of spires and monuments; springs increased flow and muddied ; utility poles and lines broken; breakages of items off shelves VII Kingston and St. Andrew. Also felt island-wide 2 dead; items thrown off shelves and broke; most were frightened; heavy furnitures shifted; water splashed out of containers and pools; much non-structural damage; few cases of structural damage VII Central Jamaica - Felt strongest at Aenon Town and Top Alston in Clarendon; Silent Hill, Manchester; Wait-a-bit and Lemon Walk, Trelawny Moderate to heavy structural damage on most vulnerable structures; some people had to be dug out of collapsed dwelling; minor injuries from falling objects