@article{WeberCardonaValenciaetal.2011,
  author    = {Weber, Marion and Cardona, A. and Valencia, V. and Altenberger, Uwe and Lopez-Martinez, M. and Tobon, M. and Zapata, Sebastian Henao and Zapata, G. and Concha, A. E.},
  title     = {Geochemistry and geochronology of the Guajira Eclogites, northern Colombia evidence of a metamorphosed primitive Cretaceous Caribbean Island-arc},
  series = {Geologica acta},
  volume    = {9},
  journal   = {Geologica acta},
  number    = {3-4},
  publisher = {Facultat de Geologia, Divisio III, Ci{\`e}ncies Experimentals i Matem{\`a}tiques, Universitat de Barcelona},
  address   = {Barcelona},
  issn      = {1695-6133},
  doi       = {10.1344/105.000001740},
  pages     = {425 -- 443},
  year      = {2011},
  abstract  = {The chemical composition of eclogites, found as boulders in a Tertiary conglomerate from the Guajira Peninsula, Colombia suggests that these rocks are mainly metamorphosed basaltic andesites. They are depleted in LILE elements compared to MORB, have a negative Nb-anomaly and flat to enriched REE patterns, suggesting that their protoliths evolved in a subduction related tectonic setting. They show island-arc affinities and are similar to primitive island-arc rocks described in the Caribbean. The geochemical characteristics are comparable to low-grade greenschists from the nearby Etpana Terrane, which are interpreted as part of a Cretaceous intra-oceanic arc. These data support evidence that the eclogites and the Etpana terrane rocks formed from the same volcano-sedimentary sequence. Part of this sequence was accreted onto the margin and another was incorporated into the subduction channel and metamorphosed at eclogite facies conditions. Ar-40-Ar-39 ages of 79.2 +/- 1.1Ma and 82.2 +/- 2.5Ma determined on white micas, separated from two eclogite samples, are interpreted to be related to the cooling of the main metamorphic event. The formation of a common volcano-sedimentary protolith and subsequent metamorphism of these units record the ongoing Late Cretaceous continental subduction of the South American margin within the Caribbean intra-oceanic arc subduction zone. This gave way to an arc-continent collision between the Caribbean and the South American plates, where this sequence was exhumed after the Campanian.},
  language  = {en}
}