Dos Santos, Ticiano J.S.Fetter, Allen H.Van Schmus, W. RandallHackspacher, Peter C. [UNESP]2014-05-272014-05-272009-12-01Geological Society Special Publication, v. 323, p. 271-281.0305-8719http://hdl.handle.net/11449/71309The c. 600 Ma Brasiliano Borborema Province of NE Brazil comprises a complex collage of Precambrian crustal blocks cut by a series of continental-scale shear zones. The predominant basement rocks in the province are 2.1-2.0 Ga Transamazonian gneisses of both juvenile and reworked nature. U-Pb zircon and Sm-Nd whole-rock studies of tonalite-trondhjemite-granodiorite basement gneisses in the NW Ceará or Médio Coreaú domain in the northwestern part of the Borborema Province indicate that this represents a continental fragment formed by 2.35-2.30 Ga juvenile crust. This block has no apparent genetic affinity with any other basement gneisses in the Borborema Province, and it does not represent the tectonized margin of the c. 2.1-2.0 Ga São Luis Craton to the NW. The petrological and geochemical characteristics, as well as the Nd-isotopic signatures of these gneisses, are consistent with their genesis in an island arc setting. This finding documents a period of crustal growth during a period of the Earth's history which is known for its tectonic quiescence and paucity of crust formation. © Geological Society of London 2009.271-281engbasement rockcontinental margincrustal evolutiongeochemistrygneissgranodioriteisland arcpetrologyPrecambriansamarium-neodymium datingshear zonetectonic evolutiontectonic settingtonalitetrondhjemiteuranium-lead datingBorboremaBrazilArtigo10.1144/SP323.13Acesso restrito2-s2.0-7494911447010401359359087340000-0003-2125-3050