7 documents found, page 1 of 1
Geology, petrography and mineral chemistry of iron oxide-apatite occurrences (I...
Parente, Clóvis Vaz; Veríssimo, César Ulisses Vieira; Botelho, Nilson Francisquini; Xavier, Roberto Perez; Menez, Jacqueline; Lino, Ramon de OliveiraIron oxide-apatite (IOA) occurrences have recently been identified in the western sector of the Neoproterozoic Santa Quitéria magmatic arc (Ceará state, northeast Brazil), close to the boundary with the Paleozoic Parnaíba Basin. The IOA mineralization is hosted by albitized metadiorites and metavolcano-sedimentary rocks, which are crosscut by a late- to post-Brasiliano/Pan-African biotite granite intrusion with...
Depósitos de escarnitos mineralizados em ferro e cobre do arco magmático de San...
Parente, Clóvis Vaz; Veríssimo, Cesar Ulisses Vieira; Botelho, Nilson Francisquini; Santos, Ticiano José Saraiva dos; Oliveira, Claudinei Gouveia deW-Mo skarns deposits in the Borborema Province have been known since the 40’s, however, until this study there were no records of Fe-Cu skarns. In Ceará State, Brazil, the first occurrences of Fe-Cu skarns were identified recently in the Magmatic Arc of Santa Quiteria, product of superposition of several magmatic arcs, ranging from juvenile arc (870 – 800 Ma), up to continental collision (625 – 600 Ma). The ska...
Nature and evolution of paleoproterozoic Sn and rare metal albitites from Centr...
Sirqueira, Ana Rita Félix; Moura, Márcia Abrahão; Botelho, Nilson Francisquini; Kyser, T. KurtEconomic and subeconomic concentrations of Sn, In, rare earth elements (REE), Ta, and Nb are known in Central Brazil, in the Goias Tin Province. The Sn-P enriched albitites studied in this paper occur in sharp contact with peraluminous granites of the Aurumina Suite (2.0–2.17 Ga) and schists of the Archean to Paleoproterozoic Ticunzal Formation, as dikes or lenses from late-stage magma of the peraluminous magma...
The Mata Azul pegmatitic field, Tocantins/Goiás, central Brazil: geology, genes...
Queiroz, Hudson de Almeida; Botelho, Nilson FrancisquiniIn Goiás and Tocantins States, Central Brazil, several granitic pegmatites were characterized and grouped for the first time. These pegmatites had been intensely explored by hand in the past, producing mainly gemstone varieties of tourmaline and beryl. Barren, beryl- and tourmaline-bearing pegmatites occur across an area of 2,000 km 2 where they intrude regional metasedimentary rocks and peraluminous granites. ...
Sr and Nd isotopic characteristics of 1.77-1.58 Ga rift-related granites and vo...
Pimentel, Márcio Martins; Botelho, Nilson FrancisquiniAs rochas supracrustais do Grupo Araí, e os granitos tipo-A associados, representam um rift continental paleo-mesoproterozóico. Duas famílias de granitos são identificadas: a mais antiga (ca. 1,77 Ga) forma pequenos plutons circulares enquanto a mais jovem (ca. 1,58 Ga), constitui corpos maiores e deformados. Dados isotópicos Sr-Nd indicam que o magmatismo félsico é predominantemente o produto de re-fusão de cr...
Evolução Geoquímica E Petrogênese De Charnockitos Ígneos No Cinturão Móvel Cost...
Celino, Joil José; Botelho, Nilson Francisquini; Celino, Joil José; Botelho, Nilson Francisquinip. 25-47; Submitted by Ana Valéria de Jesus Moura (anavaleria_131@hotmail.com) on 2011-09-02T13:59:12Z No. of bitstreams: 1 6045-33502-1-PB.pdf: 361357 bytes, checksum: 87dc19b201e0106ea76a6f1579d892cb (MD5); Made available in DSpace on 2011-09-02T13:59:12Z (GMT). No. of bitstreams: 1 6045-33502-1-PB.pdf: 361357 bytes, checksum: 87dc19b201e0106ea76a6f1579d892cb (MD5) Previous issue date: 2005; Rochas máficas e ...
Efeitos dos minerais acessórios na geoquímica de elementos terras-raras em gran...
Celino, Joil José; Botelho, Nilson Francisquini; Celino, Joil José; Botelho, Nilson Francisquinip. 1-7; Submitted by Ana Valéria de Jesus Moura (anavaleria_131@hotmail.com) on 2011-10-07T14:26:58Z No. of bitstreams: 1 Rem_ Revista Escola de Minas - Efeitos dos minerais acessórios na geoquímica de elementos terras-raras em granitóides do Comple.pdf: 293411 bytes, checksum: 5604d810401669189c92c7ec753d1543 (MD5); Made available in DSpace on 2011-10-07T14:26:58Z (GMT). No. of bitstreams: 1 Rem_ Revista Escol...