Syn-collisional peraluminous magmatism in the Rio Doce region : mineralogy, geochemistry and isotopic data of the Urucum suite (eastern Minas Gerais state, Brazil).

Submitted by Pedro Henrique da Silva Assunção (pedroassuncao94@hotmail.com) on 2014-10-23T18:23:59Z No. of bitstreams: 1 ARTIGO_SynCollisionalPeraluminous.pdf: 1007139 bytes, checksum: e0cbd7820c6eda77971d3b0353cdd649 (MD5)Submitted by Pedro Henrique da Silva Assunção (pedroassuncao94@hotmail.com) on 2014-11-18T19:26:15Z No. of bitstreams: 1 ARTIGO_SynCollisionalPeraluminous.pdf: 1007139 bytes, checksum: e0cbd7820c6eda77971d3b0353cdd649 (MD5)Approved for entry into archive by Gracilene Carvalho (gracilene@sisbin.ufop.br) on 2015-01-22T15:10:48Z (GMT) No. of bitstreams: 1 ARTIGO_SynCollisionalPeraluminous.pdf: 1007139 bytes, checksum: e0cbd7820c6eda77971d3b0353cdd649 (MD5)Made available in DSpace on 2015-01-22T15:10:57Z (GMT). No. of bitstreams: 1 ARTIGO_SynCollisionalPeraluminous.pdf: 1007139 bytes, checksum: e0cbd7820c6eda77971d3b0353cdd649 (MD5) Previous issue date: 2000The Urucum Suite granitoids (Rio Doce region, southeastern Brazil) contains four main facies: megafeldspar granites, deformed medium- to coarse-grained granites, tourmaline, and pegmatitic facies. They intrude both the staurolite-garnet-muscovite-biotite schist of the São Tomé Formation (Rio Doce Group) and the Galiléia metaluminous suite (596 ±4 Ma). Detailed structural studies suggest that the Urucum Suite emplaced during an important dextral strike-slip movement (Dl phase) of the Brasiliano orogeny (650-450Ma). Modal and chemical mineralogical variations suggest an evolution from the megafeldspar facies to the pegmatitic facies. Whole-rock geochemistry indicates the peraluminous character of the Urucum Suite granitoids, the evolution from the megafeldspar facies granites to pegmatitic facies granites and suggests the syn-collisional character of this suite. U-Pb zircon (582 ± 2 Ma) and monazite (576-573 ± 4Ma) data indicate that the Urucum Suite emplaced during the Brasiliano orogeny. The peraluminous nature of the Suite and isotopic-rich character in the Rb-Sr (87Sr/86Sr = 0.7114 to 0.7165) and Sm-Nd (eNd = -7.4 and -8.2) systems indicate that it formed by partial melting of older intermediate to felsic crustal sources. Based on early Proterozoic model-ages (2.3 to 1.8 Ga) and on 2.0 Ga U-Pb inherited signature, granitoids of the Suite are probably derived from a rocks with a long crustal residence (Transamazonian basement), without extensive mantle contribution