Neotectonics of the Caribbean

Abstract

A compilation of earthquake focal mechanism solutions together with the interpretation of inclined, intermediate-depth seismic zones, Neogene strike-slip faults, fault-controlled basins, and volcanism is used to test three existing models for the neotectonic (i.e., Neogene or post-Oligocene) development of the Caribbean. The current models, although based on different hypotheses using different data sets, are similar and suggest varying degrees of convergence between the Caribbean and either North or South American plates or convergence between the Caribbean plate and continental fragments of the northwestern corner of South America. Using model 1, previous workers have interpreted the disposition of fracture zones and magnetic anomalies in the central and South Atlantic as indicating that the Caribbean plate is being compressed by north-south convergence between the Americas with the result that it is being driven eastward relative to the Americas along strike-slip faults while producing east-west trending subductionlike convergent zones along northern and southern plate margins. Using model 2, previous workers have interpreted the azimuths of active strike-slip faults and focal mechanism solutions and closure of three-plate velocity circuits as indicating that the South American plate converges in a west-northwesterly direction on the southern margin of the Caribbean plate and has produced compressional features, while strike-slip motion dominates along the northern boundary. Using model 3, previous workers have interpreted focal mechanism solutions and the pattern of strike faulting and basin development in northwestern South America to suggest right-lateral displacement of the northwestern corner of South America relative to the craton with convergence and compression in the south central Caribbean. Our integration of geologic information on faults, basins, and volcanism considerably extends the limited record of plate interactions known from historical reports of the past few hundred years and recorded earthquakes and suggests that (1) relative motion between the North American and Caribbean plates is dominantly east-west strike-slip motion, although areas of complex internal deformation associated with restraining bend or compressional strike-slip fault segments have been identified in Jamaica, Hispaniola and Central America (2) relative motion between the South American and Caribbean plates is dominantly east-west strike-slip motion, although an area of restraining bend deformation has been identified in the Araya Peninsula of Venezuela; (3) relative motion between a triangular continental fragment of northwestern South America (the "Maracaibo Block") ranges from northwest to northeast along the south central margin of the Caribbean and appears to be driven mostly by the late Miocene-Pliocene collision of the Panama arc, although additional driving forces may include the collision of the Carnegie Ridge and/or oblique subduction (to the northeast) in Ecuador; and {4) relative motion (internal deformation) ...

Oblique collision and accretion of the Netherlands Leeward Antilles to South America

“…On the basis of our structural analysis, rotation and deformation have advanced along the diffuse plate boundary from west to east with displacement partitioning and wrench tectonics [Schubert, 1982;Mann and Burke, 1984;Macellari, 1995;Flinch et al, 1999]. Paleomagnetic analyses [Gose, 1985;Feliciano, 1993] suggest our model is also applicable at the North AmericaCaribbean plate boundary to explain the decrease in rotation from west to east.…”

Submarine landslide as the source for the October 11, 1918 Mona Passage tsunami: Observations and modeling

“…The island of Puerto Rico and the Virgin Islands comprise one of several microplates within the complexly deformed Northern Caribbean Plate Boundary Zone (Mann and Burke, 1984). The Mona Rift has been identified as an active feature serving as the microplate's western boundary.…”

The Geology of the Darien, Panama, and the late Miocene-Pliocene collision of the Panama arc with northwestern South America

“…The Darien faults manifest intraplate Pliocene deformation by northwest-oriented left-lateral strike slip (Mann and Corrigan, 1990;Mann and Kolarsky, 1995). The Panama microplate has been interpreted (Mann and Burke, 1984;Burke and §engör, 1986;Stephan et al, 1986;Mann and Kolarsky, 1995) as an example of northwestward "escape" of fault-bounded blocks involved in the ongoing collision of South America with the Caribbean plate. 2.…”