Transcript for:
Exploring Caribbean Geological Evolution

the caribbean is best known for its beautiful tropical beaches and palm trees but it also has a very interesting geological history that started about 130 million years ago the caribbean plate is the 16th largest plate and about the size of the country of india an interesting feature is that the caribbean plate is submerged beneath the sea except around its margins where most tectonic activity occurs and most people live an amazing number of political entities are found on the edges of the caribbean plate 13 independent countries and 17 dependencies of the us the netherlands france and the uk [Music] the caribbean plate is bounded north and south by strike sleep faults and subduction zones at the east and west in the south and north it's bounded by the south american plate and the north american plate respectively because the caribbean plate is moving east relative to north and south america the strike slip faults are mostly sinister in the north and mostly dextro in the south to the west the caucus plate subducts eastward beneath central america [Music] in the east the atlantic oceanic plate subducts westward beneath the lesser antilles the caribbean plate strike sleep faults are geologically diverse some segments show compression or extension as well as strike sleep behavior this is called transpression or transtension in the transtensional segments it's common to find pull apart basins one of them is the kaiman trough where we find the shortest oceanic spreading ridge in the world one that has been creating oceanic crust for about 40 million years another pull apart basins are the falcon and bonneted basins in the southern caribbean here we can also find segments of an intra-oceanic arc rotated and separated by normal faults and yesen to a thrust belt that's what formed the aruba bonaire and curacao islands and the south caribbean deformed belt all expressions of both transtension and transpression to the east and west oceanic plates subduct under the caribbean plate we know this because the earthquake's hypocenters occur at a wide range of depths between zero and 300 kilometers from the pink and purple dots going through the green dots until finally the deepest yellow dots that's what seismologists call the wadati benioff zone also above these two subduction zones is where the caribbean plates recent volcanoes are found in both central america and the lesser antilles [Music] how and when did the caribbean plate form this has been a matter of debate in the last decades there are two models that can explain how it formed the in-situ and the pacific origin models in the nc2 model the caribbean plate was created between the north american and south american plates as the two separated after pangea broke up in mesozoic times in the pacific origin model the caribbean plateau formed above a mantle plume in the pacific and migrated eastward into the gap between north and south america left by the rifting in triassic to jurassic times [Music] the greater antilles arc of cuba espanola and other small islands formed above a south dipping subduction zone in cretaceous and paleogene times moreover it collided with north america about 50 million years ago are creating the northern part of the caribbean plate to north america [Music] this collision resulted in the northern strike sleep margin we see today collisions also occurred in the south where multiple accretion of oceanic terrains have occurred since the late cretaceous to paleocene on the northwestern margin of south america [Music] today we call the result of this 130 million years of tectonic evolution the caribbean plate [Music] you