• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Master's Dissertation
DOI
10.11606/D.44.2012.tde-21122012-085416
Document
Author
Full name
Vicente Albino Manjate
E-mail
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2012
Supervisor
Committee
Tassinari, Colombo Celso Gaeta (President)
Cordani, Umberto Giuseppe
Jamal, Daúd Liace
Title in Portuguese
Geocronologia da região de Gondola-Nhamatanda (Centro de Moçambique)
Keywords in Portuguese
Cristalização
Geocronologia
Idade isocrônica
Idade modelo
Orogênese
Tafrogênese
Abstract in Portuguese
A região de Gondola-Nhamatanda localiza-se na parte limítrofe entre as províncias de Manica e Sofala, centro de Moçambique. Ela está geologicamente inserida no complexo de Bárue (Grupo de Chimoio) e na cobertura fanerozoica. O Complexo de Bárue é composto pelos Grupos supracrustais de Macossa e Chimoio intrudidos por rochas plutônicas de várias composições. Enquanto que a cobertura fanerozoica consiste de sedimentos terrestres e rochas vulcânicas associadas pertencentes ao Supergrupo do Karoo e à sequências do rifte Este Africano. A área de trabalho foi estudada em termos de petrografia; geoquímica de elementos maiores, traço e de terras raras; geocronologia e geologia isotópica pelos métdos U -Pb em zircão, Rb-Sr e Sm-Nd em rocha total e Rb-Sr em minerais para o granito de Inchope, quartzo-sienito do monte Chissui e fonolito do monte Xiluvo. Este estudo permitíu determinar os litotipos que intrudiram o grupo supracrustal de Chimoio , suas idades de cristalização e de diferenciação dos magmas que formaram seus protólitos e ainda o enquadramento tectônico. As rochas estudadas são basicamente calci -alcalinas com variações de meta à peraluminoso para os granitoides e quartzo-sienito e peralcalino para o fonolito do monte Xiluvo. Os granitoides do grupo de Chimoio foram cristalizados no Mesoproterozoico (idades U-Pb e Rb-Sr) a partir de protólitos Paleoproterozoicos ('T IND.DM' = 1,7 - 2,3 Ga); por sua vez, as rochas vulcânicas (fonolitos) do monte Xiluvo cristalizaram rápidamente no Câmbrico (idade Rb-Sr) dum protólito do Neoproterozoico-Câmbrico ('T IND.DM' = 0,54 - 0,56 Ga). Os dados isotópicos obtidos no presente estudo sugerem que as rochas do cinturão de Moçambique foram geradas por fusão parcial que provavelmente envolveu mistura ( valores negativos de ?Nd ) da crosta arqueana / paleoproterozoica e magma mesoproterozoico a 1100 Ma e sofreram retrabalhamento marcado pela aglutinação do Gondwana (orogenia Pan-Africana) e tafrogênese marcada pela fraturação do Gondwana (Rifte Este Africano ).
Keywords in English
Crystallization
Extensional process
Geochronology
isochron age
Model age
Orogenesis
Abstract in English
The region of Gondola-Nhamatanda is located at the border between the provinces of Manica and Sofala, central part of Moçambique. It is geologically inserted in the Bárue complex and the Phanerozoic cover. The Bárue complex is composed of the Macossa and Chimoio supracrustal groups intruded by plutonic rocks of various compositions, whereas the Phanerozoic cover consists of terrestrial sediments and volcanic rocks belonging to the Karoo Super-group and East African Rift Sequences. The work area was studied in terms of petrography; geochemistry of major elements, trace and rare earth elements; geochronology and isotope geology by the methods U -Pb in zircon, Rb-Sr and Sm-Nd in whole rock and Rb-Sr in minerals for the Inchope granite, Chissui mountain Quartzo-sienito and Xiluvo mountain phonolite. This study allowed to determine the lithotypes that intruded the Chimoio supracrustal group, its crystallization ages and the differentiation ages of the magmas that formed the protoliths and the tectonic framework. The studied rocks are basically calc-alkaline varying from meta to peraluminous for the granitoids and quartz-sienite and peralkaline for the mount Xiluvo phonolite. The Chimoio Group granitoids had been crystallized in the Mesoproterozoic (U-Pb and Rb-Sr ages) from Paleoproterozoic protoliths ('T IND.DM' = 1.7 - 2.4Ga); on the other hand, the volcanic rocks (phonolites) of the Xiluvo mount had crystallized fast in the Cambrian (Rb-Sr age) from a Neoproterozoic-Cambrian protolith ('T IND.DM' = 0.54 - 0.56Ga). The isotopic data, in the present study , suggest that the rocks of the Mozambique belt had been generated by partial melting that probably involved the mixture of the archean/paleoproterozoic crust and the Mesoproterozoic magma at 1100Ma and had suffered reworking marked by the Gondwana amalgamation (Pan-African orogeny) and extensional processes marked by the Gondwana break up (East African Rift).
 
WARNING - Viewing this document is conditioned on your acceptance of the following terms of use:
This document is only for private use for research and teaching activities. Reproduction for commercial use is forbidden. This rights cover the whole data about this document as well as its contents. Any uses or copies of this document in whole or in part must include the author's name.
VAMcorrigida.pdf (3.68 Mbytes)
Publishing Date
2012-12-21
 
WARNING: Learn what derived works are clicking here.
All rights of the thesis/dissertation are from the authors
Centro de Informática de São Carlos
Digital Library of Theses and Dissertations of USP. Copyright © 2001-2021. All rights reserved.