Frederico C.J. Vilalva

Dr. Frederico C.J. Vilalva

Departamento de Geologia, Universidade Federal do Rio Grande do Norte, Natal 59078-970, Brazil
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Research Focus & Metrics

Academic Career Length

17Years (2010-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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1 December 2011 in Journal of South American Earth Sciences
Verified
Journal Article
Closed access
SVSilvio Roberto Farias Vlach
Silvio Roberto Farias Vlach
OSOswaldo Siga
Oswaldo Siga
OHOssama M.M. Harara
Ossama M.M. Harara
GGGuilherme A.R. Gualda
Guilherme A.R. Gualda
Miguel Angelo Stipp BaseiMiguel Angelo Stipp Basei
Miguel Angelo Stipp Basei
Frederico C.J. VilalvaFrederico C.J. Vilalva
Frederico C.J. Vilalva


1 March 2014 in Anais da Academia Brasileira de Ciências
Verified
Journal Article
Open access
PDF file
Frederico C.J. VilalvaFrederico C.J. Vilalva
Frederico C.J. Vilalva
SVSilvio Roberto Farias Vlach
Silvio Roberto Farias Vlach
The Morro Redondo Complex is one of the most important occurrences of the Graciosa A-type Province, southern Brazil. It consists of the Papanduva and Quiriri granitic plutons and a contemporaneous bimodal volcanic association. The Papanduva Pluton includes massive and deformed peralkaline alkali-feldspar granites with Na-Ca and Na-amphiboles and clinopyroxenes. The deformed types are the most evolved rocks in the province and carry rare ‘agpaitic’ minerals, some being described for the first time in granites from Brazil. The larger Quiriri Pluton comprises massive, slightly peraluminous, biotite syeno- and monzogranites with rare Ca-amphibole. Biotite compositions are relatively homogeneous, whereas sodic amphiboles and clinopyroxenes show increasing Na and Fe3+ evolving paths. The Morro Redondo granites are ferroan, with high SiO2, alkalis and HFSE contents; the peralkaline types registering the highest fe#. LILE and HFSE abundances increase with the agpaitic index and the most evolved are HHP granites, with radiogenic heat production up to 5.7 µWm–3. Geothermobarometric estimates indicate emplacement under low pressures (∼100 MPa), at temperatures up to 850-800 °C, and relatively reduced (QFM) and oxidized (+1 < ΔQFM < +3) environments for the Papanduva and Quiriri Plutons, respectively. In both cases, melts evolved to relatively high oxidation states upon crystallization progress.



1 October 2016 in Journal of South American Earth Sciences
Verified
Journal Article
Closed access
BCBenedita Cleide Souza Campos
Benedita Cleide Souza Campos
Frederico C.J. VilalvaFrederico C.J. Vilalva
Frederico C.J. Vilalva
MNMarcos Antônio Leite Do Nascimento
Marcos Antônio Leite Do Nascimento
AGAntônio Carlos Galindo
Antônio Carlos Galindo