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	Provedor de dados Anais da ABC (AABC) (3) Autor Battilani,Gislaine A. (1) Geraldes,Mauro C. (1) Gomes,Newton S. (1) Guerra,Wilson J. (1) HARTMANN,LÉO A. (1) MCNAUGHTON,NEAL J. (1) Matos,João B. (1) RIZZOTTO,GILMAR J. (1) Ruiz,Amarildo S. (1) SANTOS,JOÃO O.S. (1) Schmitt,Renata S. (1) Teixeira,Wilson (1) Van Schumus,William R. (1) Mais... Palavra-chave Mesoproterozoic (3) Amazonian craton (2) Chapada Diamantina (1) Intracontinental rift (1) Intrusive rocks (1) Juvenile magmatism (1) Microdiamonds (1) Serra do Espinhaço (1) Tombador Formation (1) U-Pb and Sm-Nd geochronology (1) U-Pb geochronology (1) Western Amazon belt (1) Mais... Tipo do documento Info:eu-repo/semantics/article (3) Ano 2014 (1) 2007 (1) 2004 (1) País Brazil (3) Idioma Inglês (3)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 3 Primeira ... 1 ... Última The 1590-1520 Ma Cachoeirinha magmatic arc and its tectonic implications for the Mesoproterozoic SW Amazonian craton crustal evolution Anais da ABC (AABC) Ruiz,Amarildo S.; Geraldes,Mauro C.; Matos,João B.; Teixeira,Wilson; Van Schumus,William R.; Schmitt,Renata S.. Isotopic and chemical data of rocks from the Cachoeirinha suite provide new insights on the Proterozoic evolution of the Rio Negro/Juruena Province in SW Amazonian craton. Six U-Pb and Sm-Nd analyses in granitoid rocks of the Cachoeirinha suite yielded ages of 1587-1522 Ma and T DM model ages of 1.88-1.75 Ga (EpsilonNd values of -0.8 to +1.0). In addition, three post-tectonic plutonic rocks yielded U-Pb ages from 1485-1389 Ma (T DM of 1.77-1.74 Ga and EpsilonNd values from -1.3 to +1.7). Variations in major and trace elements of the Cachoeirinha suite rocks indicate fractional crystallization process and magmatic arc geologic setting. These results suggest the following interpretations: (1) The interval of 1590-1520 Ma represents an important magmatic... Tipo: Info:eu-repo/semantics/article Palavras-chave: Amazonian craton; U-Pb and Sm-Nd geochronology; Mesoproterozoic; Juvenile magmatism. Ano: 2004 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652004000400013 Tectonic evolution of the southern margin of the Amazonian craton in the late Mesoproterozoic based on field relationships and zircon U-Pb geochronology Anais da ABC (AABC) RIZZOTTO,GILMAR J.; HARTMANN,LÉO A.; SANTOS,JOÃO O.S.; MCNAUGHTON,NEAL J.. New U-Pb zircon geochronological data integrated with field relationships and an airborne geophysical survey suggest that the Nova Brasilândia and Aguapeí belts are part of the same monocyclic, metaigneous and metasedimentary belt formed in the late Mesoproterozoic (1150 Ma-1110 Ma). This geological history is very similar to the within-plate origin of the Sunsás belt, in eastern Bolivia. Thus, we propose that the Nova Brasilândia, Aguapeí and Sunsás belts represent a unique geotectonic unit (here termed the Western Amazon belt) that became amalgamated at the end of the Mesoproterozoic and originated through the reactivation of a paleo-suture (Guaporé suture zone) in an intracontinental rift environment. Therefore, its geological history involves a short,... Tipo: Info:eu-repo/semantics/article Palavras-chave: Amazonian craton; Intracontinental rift; Mesoproterozoic; Western Amazon belt; U-Pb geochronology. Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652014000100057 The occurrence of microdiamonds in Mesoproterozoic Chapada Diamantina intrusive rocks: Bahia / Brazil Anais da ABC (AABC) Battilani,Gislaine A.; Gomes,Newton S.; Guerra,Wilson J.. The origin of diamonds from Serra do Espinhaço in Diamantina region (State of Minas Gerais) and in Chapada Diamantina, Lençóis region (State of Bahia) remains uncertain, even taking into account the ample research carried out during the last decades. The lack of typical satellite minerals in both districts makes a kimberlitic source for these diamonds uncertain. In mid 18th century the occurrence of a metamorphosed igneous rock composed of martite, sericite and tourmaline was described in Diamantina region and named hematitic phyllite, considered by some researchers as a possible diamond source. Similar rocks were found in Lençóis and examined petrographically and their heavy mineral concentration was investigated by means of scanning electron microscopy... Tipo: Info:eu-repo/semantics/article Palavras-chave: Microdiamonds; Intrusive rocks; Tombador Formation; Serra do Espinhaço; Mesoproterozoic; Chapada Diamantina. Ano: 2007 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652007000200013 Registros recuperados: 3 Primeira ... 1 ... Última

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