Along the geologically complex southern boundary,[5] the Caribbean Plate interacts with the South American Plate forming Barbados, Trinidad and Tobago (all on the Caribbean Plate), and islands off the coast of Venezuela (including the Leeward Antilles) and Colombia. This boundary is in part the result of transform faulting, along with thrust faulting and some subduction. The rich Venezuelan petroleum fields possibly result from this complex plate interaction. The Caribbean Plate is moving eastward about 22 millimetres (0.87 in) per year in relation to the South American plate.[6][7] In Venezuela, much of the movement between the Caribbean Plate and the South American Plate occurs along the faults of Boconó, El Pilar and San Sebastián.[5]
The usual theory of the origin of the Caribbean Plate was confronted by a contrasting theory in 2002.
The mainstream theory holds that it is the Caribbean large igneous province (CLIP) which formed in the Pacific Ocean tens of millions of years ago, perhaps originating at the Galapagos Hotspot.[8] As the Atlantic Ocean widened, North America and South America were pushed westward, separated for a time by oceanic crust.[9] The Pacific Ocean floor subducted under this oceanic crust between the continents. The CLIP drifted into the same area, but as it was less dense and thicker than the surrounding oceanic crust, it did not subduct, but rather overrode the ocean floor, continuing to move eastward relative to North America and South America. With the formation of the Isthmus of Panama 3 million years ago, it ultimately lost its connection to the Pacific.
The more recent theory asserts that the Caribbean Plate came into being from an Atlantic hotspot which no longer exists. This theory points to evidence of the absolute motion of the Caribbean Plate which indicates that it moves westward, not east, and that its apparent eastward motion is only relative to the motions of the North American Plate and the South American Plate.[10]
First American land bridge
The Caribbean Plate began its eastward migration 80 million years ago (Ma) during the Late Cretaceous. This migration eventually resulted in a volcanic arc stretching from northwestern South America to the Yucatán Peninsula, today represented by the Aves Islands and the Lesser and Greater Antilles. This arc was the subject of constant tectonism and sea-level fluctuation, but lasted until the mid-Eocene and intermittently formed a land bridge along the eastern and northern boundaries of the Caribbean Plate.[11] What would eventually become present-day Central America, part of the western plate boundary, was still isolated in the Pacific.
58.5 to 56.5 Ma, during the Late Paleocene, a local sea-level low-stand assisted by the continental uplift of the western margin of South America, resulted in a fully operative land bridge over which several groups of mammals apparently took part in an interchange. For example, specimens have been assigned to xenarthra, didelphidae, and phorusrhacidae from Eocene North America and Europe (although these have been criticized),[11][12] and Peradectes from Paleocene South America.[13]
The Great American Interchange in which land and freshwater fauna migrated between North America and South America via the uplifted western margin of the Caribbean Plate (Central America) was a later event, which peaked dramatically around 2.6 million years (Ma) ago during the Piacenzian age.
^Deiros D (2000) [Determination of Displacement Between Caribbean and South American Plates in Venezuela using Global Positioning System (GPS) data.] Geological Code of Venezuela. (in Spanish)
^Pérez OJ, Bilham R, Bendick R, Hernández N, Hoyer M, Velandia J, Moncayo C y Kozuch M (2001) Relative velocity between the Caribbean and South America Plates from observations Within the Global Positioning System (GPS) in northern Venezuela.(in Spanish)
Gómez Tapias, Jorge; Montes Ramírez, Nohora E.; Almanza Meléndez, María F.; Alcárcel Gutiérrez, Fernando A.; Madrid Montoya, César A.; Diederix, Hans (2015). Geological Map of Colombia. Servicio Geológico Colombiano. pp. 1–212. Retrieved 2019-10-29.