Muestra métricas de impacto externas asociadas a la publicación. Para mayor detalle:
| Indexado |
|
||||
| DOI | 10.1016/J.JSAMES.2011.02.002 | ||||
| Año | 2011 | ||||
| Tipo | artículo de investigación |
Citas Totales
Autores Afiliación Chile
Instituciones Chile
% Participación
Internacional
Autores
Afiliación Extranjera
Instituciones
Extranjeras
The Maria da Fe Shear Zone (MFSZ) is a sinistral strike-slip kilometric-scale structure developed in the late Neoproterozoic during the assembly of Gondwana. The MFSZ development is related to the NW SE collision between the sao Francisco Paleocontinent and the Rio Negro Magmatic Arc, which formed the Ribeira Belt. This paper describes the shear zone in detail, concluding that the orientation and age are consistent with NW SE shortening during the afore mentioned collision. A U-Pb SHRIMP Concordia age of 586.9 +/- 8.7 Ma is reported from zircon grains of a granitic dyke that crystallised synkinematically to the main tectonic activity of the shear zone. Another group of zircon grains from the same sample generated an upper intercept age of 2083 +/- 43 Ma anchored in the younger Concordia age. These zircon grains are interpreted as relict grains of the basement from which the granite dyke was generated by partial melting. The temperature during mylonitization in the MFSZ was estimated in the range from 450 to 600 degrees C, based on microstructures in quartz and feldspar. An earlier collision in the same region, between 640 and 610 Ma, led to an extensive nappe-stack with tectonic transport to ENE, integrating the southern Brasilia Belt. One of the thrust zones between these nappes in the studied area is the Cristina Shear Zone with mylonites that were generated under upper amphibolite to granulite facies conditions. Brittle-ductile E W metric-scale shear zones are superimposed on the MFSZ, which were active in similar, but probably slightly cooler, metamorphic conditions (approximate to 500 degrees C). (C) 2011 Elsevier Ltd. All rights reserved.
| Ord. | Autor | Género | Institución - País |
|---|---|---|---|
| 1 | Zuquim, M. P. S. | - |
UNIV FED RIO DE JANEIRO - Brasil
Universidade Federal do Rio de Janeiro - Brasil |
| 2 | Trouw, R. A. J. | Hombre |
UNIV FED RIO DE JANEIRO - Brasil
Universidade Federal do Rio de Janeiro - Brasil |
| 3 | Trouw, C. C. | Hombre |
BHP Billiton - Chile
|
| 4 | Tohver, E. | - |
Univ Western Australia - Australia
University of Western Australia - Australia The University of Western Australia - Australia |
| Fuente |
|---|
| Conselho Nacional de Desenvolvimento Científico e Tecnológico |
| Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) |
| Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico |
| Agradecimiento |
|---|
| The authors acknowledge the Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) for financial support for field work and MPSZ acknowledges CNPq for the MSc scholarship. The facilities, scientific and technical assistance of the Australian Microscopy & Microanalysis Research Facility at the Centre for Microscopy, Characterisation & Analysis, the University of Western Australia, a facility funded by the University, State and Commonwealth Governments are acknowledged for the geochronological preparation and VP-FESEM Imagery. CCT acknowledges Curtin University of Technology for its facilities and technical assistance for the SHRIMP II analyses and BHP Billiton for financing the analyses, related to his PhD. MPSZ acknowledges the Brazilian Geological Survey (CPRM), especially F.M. Faleiros for the support with the C-axis analysis. The authors also thank Dr. Reinhardt A. Fuck and anonymous reviewers, whose comments were of great help to improve this manuscript. |
| The authors acknowledge the Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) for financial support for field work and MPSZ acknowledges CNPq for the MSc scholarship. The facilities, scientific and technical assistance of the Australian Microscopy & Microanalysis Research Facility at the Centre for Microscopy, Characterisation & Analysis, the University of Western Australia, a facility funded by the University, State and Commonwealth Governments are acknowledged for the geochronological preparation and VP-FESEM Imagery. CCT acknowledges Curtin University of Technology for its facilities and technical assistance for the SHRIMP II analyses and BHP Billiton for financing the analyses, related to his PhD. MPSZ acknowledges the Brazilian Geological Survey (CPRM), especially F.M. Faleiros for the support with the C-axis analysis. The authors also thank Dr. Reinhardt A. Fuck and anonymous reviewers, whose comments were of great help to improve this manuscript. |