Caribbean tectonics encompasses the majority of the Caribbean Sea and southeast Pacific regions that include the Caribbean, Nazca, North Andean, Panama plates and the Galapagos and Caribbean microplates (Figure 1). These plates are dominantly oceanic and contain a diversity of interesting tectonic features such as all three of the dominant types of plate boundaries, multiple triple junctions, hotspots and more. Given the dense population and tectonic activity surrounding many plate boundaries in this region, this area has garnered much attention from the scientific community due to its natural hazard risk (Benford et al. 2012) and is also the location of the first discovered oceanic black smoker and also the largest earthquake ever recorded (Tao et al., 2011, Kanamori & Cipar 1976).
Although the formation of most of the plates in the Caribbean region can be traced back to events in the Cenozoic (Lonsdale 2005, Searle 1989, Bachman 2001, Lonsdale 1988, Cediel & Shaw 2003), most of the present-day plates can be thought of as fragments of their respective precursors (Lonsdale 2005, Lonsdale 1988, Searle 1989). The Nazca plate, for example is a remnant of the former Farallon plate from which it split during inter-plate spreading ~23 Ma (Lonsdale 2005, Searle 1989). Moreover, plates such as the North Andean plate contain sedimentary rocks spanning from ~199 to ~23 Ma (Ramos, 1999), indicating lengthy development of the rigid body that makes up the plate. |
Figure 1. Map drawing out the major plate boundaries surrounding the Caribbean tectonic region. Source: thewatchers.com
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While not one single history can describe the formation of all of the plates in the Caribbean, key tectonic events such as the shift in direction of divergence along the East Pacific Rise could have caused consequent stresses that rifted precursor plates into their current segments (Ray et al., 2012).
Current Plate Motions
Today, the plate motions of the Caribbean tectonic region exhibit some of the fastest and complex motions on the planet. All of the current plate motions, besides the South Jamaican microplate, are summarized in Table 1. Notably, the Nazca plate exhibits the world’s fastest rate of convergence along its eastern boundary with South America (Figure 2) and the world’s fastest rate of divergence at the East Pacific Rise (Norabueana et al., 1999). Arguably the most tectonically complex areas in the Caribbean tectonic region are the Galapagos and Caribbean microplates, the former exhibiting significant rotational motion. Located along a triple-rift junction and along complex systems of transform-faults respectively, much of their movement has yet to be resolved in a coherent tectonic model (Smith et al., 2009).
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As mentioned earlier, the Caribbean tectonic region has garnered much interest from the scientific and politico-economic groups. This region is heavily populated, especially around the Caribbean Sea and the west coast of South America, and exhibits much tectonic activity (Kanamor & Cipar, 1976, DeMets & Wiggins-Grandison, 2006) and volcanism, leading to natural hazard risks for the surrounding population (Figure 3). Furthermore, the region is filled with natural resources that formed as a consequence of the surrounding tectonic activity (Nelson, 2011), and is also a popular tourist destination around the rugged Andes and warm Caribbean Sea.
Future tectonics in this region includes several interesting scenarios that could affect current plate motions. First, the height of the oceanic ridge at the transition from the Nazca Ridge to the Easter Seamount Chain is significantly greater than elsewhere on the ridge. Given the idea that buoyancy is playing a major role in the “flat-slab” subduction of the Nazca plate (Gutscher, 2002). perhaps the angle of the subduction would decrease even further with the subduction of more buoyant ridge material.
References:
Bachmann, Raik. (2001). The Caribbean plate and the question of its formation. Institute of Geology, University of Mining and Technology Freiberg Department of Tectonophysics
Benford, B., DeMets, C., Calais, E., 2012, GPS estimates of microplate motions, northern Caribbean: evidence for a Hispaniola microplate and implications for earthquake hazard: Geophysical Journal International, v. 191, p. 481-490
Bird, P. (2003). An updated digital model of plate boundaries. Geochemistry, Geophysics, Geosystems, 4(3).
Cardona, A., Valencia, V. A., Bayona, G., Duque, J., et al. (2011). Early-subduction-related orogeny in the northern Andes: Turonian to Eocene magmatic and provenance record in the Santa Marta Massif and Rancheria Basin, northern Columbia. Terra Nova, 23, 26-34.
Cediel, F., R. P. Shaw, and C. Ca ́ceres. (2003). Tectonic assembly of the Northern Andean Block. The Circum-Gulf of Mexico and the Caribbean: Hydrocarbon habitats, basin formation, and plate tectonics: AAPG Memoir 79, 815–848.
DeMets, C., Wiggins-Grandison, M. (2006). Deformation of Jamaica and motion of the Gonâve microplate from GPS and seismic data. Geophysics Journal International, v. 168, p. 362-378
Gutscher, M. (2002). Andean subduction styles and their effect on thermal structure and interplate coupling. Journal of South American Earth Sciences, 15(1), 3-10.
Kanamori, H., & Cipar, J. J. (1974). Focal process of the great chilean earthquake may 22, 1960. Physics of the Earth and Planetary Interiors, 9(2), 128-136.
Lonsdale, P. (1988). Structural Pattern of the Galapagos Microplate and Evolution of the Galapagos Triple Junctions, Journal of Geophysical Research, 93(B11), 13551-13574.
Lonsdale, P. (2005). Creation of the cocos and nazca plates by fission of the farallon plate. Tectonophysics, 404(3-4), 237-264.
Nelson, C. E., et al. (2011). The metallogenic evolution of the Greater Antilles. Geologica Acta: an international earth science journal, 9.3, 229-264.
Norabuena, E. O., Dixon, T. H., Stein, S., & Harrison, C. G. A. (1999). Decelerating nazca-south america and nazca-pacific plate motions. Geophysical Research Letters, 26(22), 3405-3408.
Ramos, V. A. (1999). Plate tectonic setting of the Andean Cordillera. Episodes, 22(3), 183-190.Reed, D. L., Silver, E. A., Tagudin, J. E., Shipley, T. H., Vrolijk, P. (1989).
Ray, J. S., Mahoney, J. J., Duncan, R. A., Ray, J., Wessel, P., & Naar, D. F. (2012). Chronology and geochemistry of lavas from the nazca ridge and easter seamount chain; an approximately 30 myr hotspot record. Journal of Petrology, 53(7), 1417-1448.
Searle, R. C., Francheteau, J. (1985). Morphology and Tectonics of the Galapagos Triple Junction, Marine Geophysical Researches, 8, 95-129.
Searle, R. C., Francheteau, J. (1985). Morphology and Tectonics of the Galapagos Triple Junction, Marine Geophysical Researches, 8, 95-129.
Smith, D. K., Schouten, H., Cann, J. R., Zhu, W., Montesi, L. G., Mitchell, G. A. (2009). The Galapagos Microplate Revealed, American Geophysical Union Fall Meeting 2009.
Sobolev, S. V., & Babeyko, A. Y. (2005). What drives orogeny in the andes? Geology (Boulder), 33(8), 617-620.
Tao, C., Li, H., Wu, G., Su, X., Zhang, G. (2011). First Hydrothermal Active Vent Discovered on the Galapagos Microplate, American Geophysical Union Fall Meeting 2011.
Benford, B., DeMets, C., Calais, E., 2012, GPS estimates of microplate motions, northern Caribbean: evidence for a Hispaniola microplate and implications for earthquake hazard: Geophysical Journal International, v. 191, p. 481-490
Bird, P. (2003). An updated digital model of plate boundaries. Geochemistry, Geophysics, Geosystems, 4(3).
Cardona, A., Valencia, V. A., Bayona, G., Duque, J., et al. (2011). Early-subduction-related orogeny in the northern Andes: Turonian to Eocene magmatic and provenance record in the Santa Marta Massif and Rancheria Basin, northern Columbia. Terra Nova, 23, 26-34.
Cediel, F., R. P. Shaw, and C. Ca ́ceres. (2003). Tectonic assembly of the Northern Andean Block. The Circum-Gulf of Mexico and the Caribbean: Hydrocarbon habitats, basin formation, and plate tectonics: AAPG Memoir 79, 815–848.
DeMets, C., Wiggins-Grandison, M. (2006). Deformation of Jamaica and motion of the Gonâve microplate from GPS and seismic data. Geophysics Journal International, v. 168, p. 362-378
Gutscher, M. (2002). Andean subduction styles and their effect on thermal structure and interplate coupling. Journal of South American Earth Sciences, 15(1), 3-10.
Kanamori, H., & Cipar, J. J. (1974). Focal process of the great chilean earthquake may 22, 1960. Physics of the Earth and Planetary Interiors, 9(2), 128-136.
Lonsdale, P. (1988). Structural Pattern of the Galapagos Microplate and Evolution of the Galapagos Triple Junctions, Journal of Geophysical Research, 93(B11), 13551-13574.
Lonsdale, P. (2005). Creation of the cocos and nazca plates by fission of the farallon plate. Tectonophysics, 404(3-4), 237-264.
Nelson, C. E., et al. (2011). The metallogenic evolution of the Greater Antilles. Geologica Acta: an international earth science journal, 9.3, 229-264.
Norabuena, E. O., Dixon, T. H., Stein, S., & Harrison, C. G. A. (1999). Decelerating nazca-south america and nazca-pacific plate motions. Geophysical Research Letters, 26(22), 3405-3408.
Ramos, V. A. (1999). Plate tectonic setting of the Andean Cordillera. Episodes, 22(3), 183-190.Reed, D. L., Silver, E. A., Tagudin, J. E., Shipley, T. H., Vrolijk, P. (1989).
Ray, J. S., Mahoney, J. J., Duncan, R. A., Ray, J., Wessel, P., & Naar, D. F. (2012). Chronology and geochemistry of lavas from the nazca ridge and easter seamount chain; an approximately 30 myr hotspot record. Journal of Petrology, 53(7), 1417-1448.
Searle, R. C., Francheteau, J. (1985). Morphology and Tectonics of the Galapagos Triple Junction, Marine Geophysical Researches, 8, 95-129.
Searle, R. C., Francheteau, J. (1985). Morphology and Tectonics of the Galapagos Triple Junction, Marine Geophysical Researches, 8, 95-129.
Smith, D. K., Schouten, H., Cann, J. R., Zhu, W., Montesi, L. G., Mitchell, G. A. (2009). The Galapagos Microplate Revealed, American Geophysical Union Fall Meeting 2009.
Sobolev, S. V., & Babeyko, A. Y. (2005). What drives orogeny in the andes? Geology (Boulder), 33(8), 617-620.
Tao, C., Li, H., Wu, G., Su, X., Zhang, G. (2011). First Hydrothermal Active Vent Discovered on the Galapagos Microplate, American Geophysical Union Fall Meeting 2011.