Please use this identifier to cite or link to this item:
Full metadata record
DC FieldValueLanguage
dc.contributor.authorRIZZOTTO, Gilmar Josépt_BR
dc.contributor.authorALVES, Cleber Ladeirapt_BR
dc.contributor.authorRIOS, Francisco Senept_BR
dc.contributor.authorBARROS, Marcia Aparecida de Sant’Anapt_BR
dc.identifier.citationRIZZOTTO, Gilmar Jose; ALVES, Cleber Ladeira; RIOS, Francisco Sene; BARROS, Marcia Aparecida de Sant’Ana. The Nova Monte Verde metamorphic core complex: Tectonic implications for the southern Amazonian craton. Journal of South American Earth Sciences, n. 91, p. 154-172, 2019.en
dc.description.abstractThe Nova Monte Verde metamorphic core complex is an arched structure located in the southern portion of the Rio Negro-Juruena geochronological Province and is part of a belt of metamorphic rocks containing gneiss and migmatite domes exhumed during Statherian extension of rifted Ventuari-Tapajós crust. This metamorphic core is bordered, both to the north and south, by felsic volcanic and plutonic rocks intensely foliated near the metamorphic core and becoming progressively undeformed as one moves away from the metamorphic core. U-Pb analyses of zircon and monazite from migmatites exposed in the core of the complex, coupled with a detailed structural analysis, enlighten the timing and duration of migmatite crystallization, indicating that crystallization, extensional deformation and exhumation of the core-complex were coeval. Analysis of a high melt fraction from migmatites outcroping near Bacaeri Farm suggest that the Nova Monte Verde metamorphic core complex records a history of neosome formation spanning at least 37 Ma, as indicated by 206Pb/238U ages (1800-1763Ma) for new zircon growth attributed to migmatization. Monazite from two samples yielded U-Pb ages of 1798 ± 29 Ma for the aluminous metatexite and 1754 ± 11 Ma for sillimanite-biotite metatexite. The former is interpreted as the metamorphic peak and main generation of leucosomes, and the latter as the second phase of partial melting or as an alternative, the timing of cooling and exhumation of metamorphic core complex. Crystallization of the Nova Monte Verde migmatites was therefore coeval in part with upper crustal extension and ductile flow of the mid-crust, suggesting that crustal anatexis was widespread over much of the mid-crust during Statherian time (∼1800-1760Ma). Therefore, the tectonic history of the Nova Monte Verde core complex involved regional extension and exhumation of high-grade metamorphic rocks by transtensional tectonics. The following results are at least more compatible with, if not suggestive of, a continental rift setting than the traditionally accepted continental arc setting.pt_BR
dc.titleThe Nova Monte Verde metamorphic core complex: Tectonic implications for the southern Amazonian Cratonen
dc.localS. l.pt_BR
dc.subject.enAMAZONIAN CRATONen
dc.subject.enCORE COMPLEXen
dc.subject.enCRUSTAL EXTENSIONen
Appears in Collections:Artigos de Periódicos

Files in This Item:
File Description SizeFormat 
Arquivo ART_CENTIFICO_1.pdfArtigo principal7,38 MBAdobe PDFThumbnail

Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.