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The early interaction between the Caribbean Plateau and the NW South American Plate
Author(s) -
Vallejo Cristian,
Spikings Richard A.,
Luzieux Leonard,
Winkler Wilfried,
Chew David,
Page Laurence
Publication year - 2006
Publication title -
terra nova
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.353
H-Index - 89
eISSN - 1365-3121
pISSN - 0954-4879
DOI - 10.1111/j.1365-3121.2006.00688.x
Subject(s) - geology , subduction , magmatism , plateau (mathematics) , continental collision , collision , cretaceous , zircon , oceanic crust , paleontology , crust , continental margin , continental crust , tectonics , mathematical analysis , mathematics , computer security , computer science
The determination of accurate and precise ages for the timing of collision between oceanic plateaus and continental crust requires an understanding of how the indenting and buttressing plates respond to the collision. We present geochronological, thermochronological, geochemical and isotopic analyses of magmatic rocks from the Ecuadorian Andes, which relate to the collision of the Late Cretaceous Caribbean Plateau and Great Arc sequence with NW South America. The cessation of subduction magmatism during 65–64 Ma beneath the eastern edge of Caribbean Plateau was synchronous with accelerated surface uplift and exhumation within the buttressing continental margin during 75–65 Ma. We interpret this as the collision of the leading edge of the Caribbean Plateau and arc sequence with the South American Plate at 75–65 Ma. A U/Pb (zircon) SHRIMP age of 87.10 ± 1.66 (2 σ ) Ma, yielded by an accreted fragment of the plateau, precludes previous estimates of collision at 85–80 Ma if the plateau erupted above the Galápagos hotspot. Terra Nova, 18, 264–269, 2006