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Greater Antilles: Northern Caribbean Plate Kinematics Tectonic Setting |
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Current Tectonic Setting of the Greater Antilles Since the middle Eocene (about 45 mya), the North American plate has been subducting below the Caribbean plate east of Hispaniola, resulting in the island arc of the Lesser Antilles and its associated volcanism (Dolan et al., 1998; Gibbs, 2001). This eastern motion results in left-lateral movement along the northern portion of the Caribbean plate, composed of the Greater Antilles (Dolan et al., 1998). There is much debate as to the exact direction of the relative motion between these two plates. Some argue for east-west left-lateral strike-slip, or northeast-southwest oblique convergence (Dolan et al., 1998). This fault system extends over 3200 km from the Lesser Antilles arc in the east to the Middle American trench off the western coast of southern Mexico and northern Central America (Mann, 2001). This faulting has thrust Jamaica, Hispaniola, and Puerto Rico above sea level, creating the Greater Antilles.
Historical Tectonic Setting of the Greater Antilles During the Cretaceous, an early phase of rifting formed the Gulf of Mexico by divergence which occurred before the Caribbean Plate began converging (Burke et al, 1984). In the Late Cretaceous, convergence on the now northern and southern Caribbean margins produced arc-systems and moved the present Caribbean ocean floor, which is an oceanic plateau, out of the Pacific (Burke et al, 1984). Cenozoic convergence has aided in the movement eastward of 1000 km in the Lesser Antilles and Central America (Burke et al, 1984). This movement is distributed in wide plate boundary zones of the Caribbean with respect to North and South America (Burke et al, 1984). The moderate internal deformation of the Caribbean plate is most likely due to its oceanic plateau characteristics, meaning that it acts mechanically like a plate that is intermediate between a normal ocean floor and continent (Burke et al, 1984). This plateau is composed of basalts, which some suggest formed over the Galapagos hot spot (Significant, 2001; Iturralde-Vinent, 2000).
Cuba
Jamaica
Hispaniola
Puerto Rico
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