{"id":57,"date":"2018-01-09T01:45:19","date_gmt":"2018-01-09T01:45:19","guid":{"rendered":"http:\/\/virtualuppermantle.info\/news\/?p=57"},"modified":"2026-01-25T10:49:29","modified_gmt":"2026-01-25T10:49:29","slug":"central-america-tectonic-setting","status":"publish","type":"post","link":"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/","title":{"rendered":"Central America Tectonic Setting"},"content":{"rendered":"<p>&nbsp;<\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_82_2 counter-hierarchy ez-toc-counter ez-toc-grey ez-toc-container-direction\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<label for=\"ez-toc-cssicon-toggle-item-69f3881a8446b\" class=\"ez-toc-cssicon-toggle-label\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #999;color:#999\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #999;color:#999\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/label><input type=\"checkbox\"  id=\"ez-toc-cssicon-toggle-item-69f3881a8446b\" checked aria-label=\"Toggle\" \/><nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-1'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#Introduction\" >Introduction<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-1'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#Seismotectonics_of_the_Caribbean_Region_and_Vicinity\" >Seismotectonics of the Caribbean Region and Vicinity<\/a><ul class='ez-toc-list-level-2' ><li class='ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#The_northern_margin_of_the_Caribbean_plate\" >The northern margin of the Caribbean plate.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#The_deep_Puerto_Rico_Trench_and_subduction_zone\" >The deep Puerto Rico Trench and subduction zone.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#The_motion_between_the_North_America_plate_and_the_Caribbean_plate\" >The motion between the North America plate and the Caribbean plate.<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#The_Lesser_Antilles_Trench\" >The Lesser Antilles Trench.<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#The_Caribbean_plate_boundary_with_the_South_America_plate\" >The\u00a0Caribbean plate boundary with the South America plate.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#The_plate_boundary_off_shore_of_Colombia\" >The plate boundary off shore of Colombia.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#The_western_coast_of_Central_America\" >The western coast of Central America.<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#The_boundary_between_the_Cocos_and_Nazca_plates\" >The boundary between the Cocos and Nazca plates.<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-1'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/#A_Great_Earthquake_offshore_of_Chiapas_Mexico\" >A Great Earthquake offshore of Chiapas, Mexico.<\/a><\/li><\/ul><\/nav><\/div>\n<h1><span class=\"ez-toc-section\" id=\"Introduction\"><\/span>Introduction<span class=\"ez-toc-section-end\"><\/span><\/h1>\n<p>Extensive diversity and complexity of tectonic regimes characterizes the perimeter of the <strong>Caribbean plate<\/strong>, involving no fewer than four major plates (<strong>North America\u00a0plate<\/strong>, <strong>South America\u00a0plate<\/strong>, <strong>Nazca\u00a0plate<\/strong>, and <strong>Cocos\u00a0plate<\/strong>). Inclined zones of deep earthquakes (<strong>Wadati-Benioff zones<\/strong>), ocean trenches, and arcs of volcanoes clearly indicate <strong>subduction of oceanic lithosphere<\/strong> 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 <strong>transform fault<\/strong> and pull-apart basin tectonics.<br \/>\n<!--more--><\/p>\n<h1><span class=\"ez-toc-section\" id=\"Seismotectonics_of_the_Caribbean_Region_and_Vicinity\"><\/span>Seismotectonics of the Caribbean Region and Vicinity<span class=\"ez-toc-section-end\"><\/span><\/h1>\n<figure id=\"attachment_52\" aria-describedby=\"caption-attachment-52\" style=\"width: 600px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"wp-image-52 size-full\" src=\"http:\/\/virtualmantle.com\/news\/wp-content\/uploads\/2018\/01\/600px-Map-of-Tectonic-Summary-Region.jpg\" alt=\"Map of Tectonic Summary Region\" width=\"600\" height=\"388\" srcset=\"http:\/\/www.virtualmantle.com\/news\/wp-content\/uploads\/2018\/01\/600px-Map-of-Tectonic-Summary-Region.jpg 600w, http:\/\/www.virtualmantle.com\/news\/wp-content\/uploads\/2018\/01\/600px-Map-of-Tectonic-Summary-Region-300x194.jpg 300w\" sizes=\"auto, (max-width: 709px) 85vw, (max-width: 909px) 67vw, (max-width: 984px) 61vw, (max-width: 1362px) 45vw, 600px\" \/><figcaption id=\"caption-attachment-52\" class=\"wp-caption-text\">Map of Tectonic Summary Region<\/figcaption><\/figure>\n<h2><span class=\"ez-toc-section\" id=\"The_northern_margin_of_the_Caribbean_plate\"><\/span>The northern margin of the Caribbean plate.<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Along the <strong>northern margin of the Caribbean plate<\/strong>, 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 <strong>Cayman Trench<\/strong>.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"The_deep_Puerto_Rico_Trench_and_subduction_zone\"><\/span>The deep Puerto Rico Trench and subduction zone.<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>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 <strong>Puerto Rico Trench<\/strong> 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 <strong>May 2, 1787<\/strong> 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 <strong>August 4, 1946 M8.0 Samana earthquake<\/strong> in northeastern Hispaniola and the <strong>July 29, 1943 M7.6 Mona Passage earthquake<\/strong>, both of which were shallow thrust fault earthquakes.<\/p>\n<p><a href=\"#top\">To Top<\/a><\/p>\n<h2><span class=\"ez-toc-section\" id=\"The_motion_between_the_North_America_plate_and_the_Caribbean_plate\"><\/span>The motion between the North America plate and the Caribbean plate.<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>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.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"The_Lesser_Antilles_Trench\"><\/span>The Lesser Antilles Trench.<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>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 <strong>Lesser Antilles Trench<\/strong> at rates of approximately <strong>20 mm\/yr<\/strong>. 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<strong> February 8, 1843<\/strong>, with a suggested magnitude greater than 8.0. The largest recent intermediate-depth earthquake to occur along the Lesser Antilles arc was the <strong>November 29, 2007 M7.4 Martinique earthquake northwest of Fort-De-France<\/strong>.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"The_Caribbean_plate_boundary_with_the_South_America_plate\"><\/span>The\u00a0Caribbean plate boundary with the South America plate.<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The southern Caribbean plate boundary with the South America plate strikes east-west across Trinidad and western Venezuela at a relative rate of approximately <strong>20 mm\/yr<\/strong>. This boundary is characterized by major transform faults, including the <strong>Central Range Fault<\/strong> and the<strong> Bocon\u00f3-San Sebastian-El Pilar Faults<\/strong>, and shallow seismicity. Since 1900, the largest earthquakes to occur in this region were the <strong>October 29, 1900 M7.7 Caracas earthquake<\/strong>, and the <strong>July 29, 1967 M6.5 earthquake<\/strong> 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 (M&lt;6.0) earthquakes of shallow to intermediate depth.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"The_plate_boundary_off_shore_of_Colombia\"><\/span>The plate boundary off shore of Colombia.<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>The plate boundary off shore of Colombia is also characterized by convergence, where the <strong>Nazca plate<\/strong> subducts beneath <strong>South America<\/strong> towards the east at a rate of approximately <strong>65 mm\/yr<\/strong>. The <strong>January 31, 1906 M8.5<\/strong> earthquake occurred on the shallowly dipping megathrust interface of this plate boundary segment.<\/p>\n<p><a href=\"#top\">To Top<\/a><\/p>\n<h2><span class=\"ez-toc-section\" id=\"The_western_coast_of_Central_America\"><\/span>The western coast of Central America.<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>Along the western coast of Central America, the <strong>Cocos plate<\/strong> subducts towards the east beneath the <strong>Caribbean plate<\/strong> at the <strong>Middle America Trench<\/strong>. Convergence rates vary between <strong>72-81 mm\/yr<\/strong>, 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 <strong>September 7, 1915 M7.4 El Salvador<\/strong> and the <strong>October 5, 1950 M7.8 Costa Rica<\/strong> events.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"The_boundary_between_the_Cocos_and_Nazca_plates\"><\/span>The boundary between the Cocos and Nazca plates.<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>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 <strong>Panama Fracture Zone<\/strong>. The Panama Fracture Zone terminates in the south at the <strong>Galapagos rift zone<\/strong> and in the north at the <strong>Middle America trench<\/strong>, where it forms part of the <strong>Cocos-Nazca-Caribbean triple junction<\/strong>. Earthquakes along the Panama Fracture Zone are generally shallow, low- to intermediate in magnitude (M&lt;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 <strong>July 26, 1962 M7.2 earthquake<\/strong>.<\/p>\n<h1><span class=\"ez-toc-section\" id=\"A_Great_Earthquake_offshore_of_Chiapas_Mexico\"><\/span>A Great Earthquake offshore of Chiapas, Mexico.<span class=\"ez-toc-section-end\"><\/span><\/h1>\n<p>A Great Earthquake offshore of Chiapas, Mexico is one of four M 8 or greater earthquakes ever recorded along the subduction zone forming the <strong>Middle American Trench<\/strong>. There has recently been some seismic activity to the east of this current M 8.1 earthquake. These earthquakes happened near the boundary between the North America (NAP) and Caribbean (CP) upper plates.<br \/>\nThis M 8.1 earthquake happened in a region of the subduction zone that is interpreted to have a higher coupling ratio than further to the south (higher proportion of the plate convergence rate is accumulated as elastic strain due to seismogenic coupling of the megathrust fault). Faults that are aseismic (fully slipping) have a coupling ratio of zero. The Polochic-Motagua fault zone marks this NAP-CP boundary. The recent seismicity offshore of Guatemala (June 2017) comprised a series of thrust earthquakes along the upper megathrust, along with some down-dip extensional faulting.<br \/>\nThis M 8.1 earthquake is deeper than the megathrust fault and has an extensional moment tensor. This is not a megathrust earthquake, but is related to slip on a fault in the downgoing Cocos plate. At this depth, it may be due to bending in the downgoing oceanic lithosphere.<\/p>\n<p><a href=\"#top\">To Top<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>&nbsp; Introduction Extensive diversity and complexity of tectonic regimes characterizes the perimeter of the Caribbean plate, involving no fewer than four major plates (North America\u00a0plate, South America\u00a0plate, Nazca\u00a0plate, and Cocos\u00a0plate). 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 &hellip; <a href=\"http:\/\/www.virtualmantle.com\/news\/central-america-tectonic-setting\/\" class=\"more-link\">Continue reading<span class=\"screen-reader-text\"> &#8220;Central America Tectonic Setting&#8221;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":130,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[4,13,12],"tags":[19,14,15,17,18,20,16],"class_list":["post-57","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-earthquakes","category-seismotectonics","category-tectonics","tag-boundary","tag-earhquakes","tag-fault-zone","tag-fracture-zone","tag-plates","tag-subduction","tag-trench"],"_links":{"self":[{"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/posts\/57","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/comments?post=57"}],"version-history":[{"count":12,"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/posts\/57\/revisions"}],"predecessor-version":[{"id":156,"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/posts\/57\/revisions\/156"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/media\/130"}],"wp:attachment":[{"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/media?parent=57"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/categories?post=57"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.virtualmantle.com\/news\/wp-json\/wp\/v2\/tags?post=57"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}