The Statherian itabirite-bearing sequence from the Morro Escuro Ridge, Santa Maria de Itabira, Minas Gerais, Brazil
MetadataShow full item record
The itabirite-bearing metasedimentary sequence from Morro Escuro Ridge comprises the basal units of the Espinhaço Supergroup and makes up a small tectonic inlier developed during one of the Brasiliano orogenic events (800-500Ma), amongst horses of the Archean TTG gneisses, including sheared granites of the anorogenic Borrachudos Suite (~1700Ma). The metasedimentary rocks are comprised of low-to intermediate-amphibolite facies schists, quartzites, conglomerates and banded iron formation (itabirite) correlatable with the sequences of the Serro Group, which underlies the metasedimentary rocks of the Espinhaço Supergroup in the Serra da Serpentina Ridge. A maximum Statherian deposition age (1668Ma) was established using SHRIMP U-Pb isotopic constraints on zircon grains from conglomerate and quartzite units overlying the itabirite. The itabirite is predominantly hematitic and its geochemical characteristics are typical of a Lake Superior-type BIF deposited in a platformal, suboxic to anoxic environment distant from Fe-bearing hydrothermal vents. Close to the contact zone with amphibolites of the Early Neoproterozoic Pedro Lessa mafic suite, an increase of the magnetite content and crystallization of metasomatic Mg-hornblende and Ce-allanite can be observed. These mineralogical changes developed preferentially along the igneous contact zone but are probably co-genetic with the formation of alteration haloes in zircon grains during the Neoproterozoic Brasiliano orogeny (506±6Ma).
Showing items related by title, author, creator and subject.
Crous, P.; Wingfield, M.; Guarro, J.; Cheewangkoon, R.; van der Bank, M.; Swart, W.; Stchigel, A.; Cano-Lira, J.; Roux, J.; Madrid, H.; Damm, U.; Wood, A.; Shuttleworth, L.; Hodges, C.; Munster, M.; de Jesús Yáñez-Morales, M.; Zúñiga-Estrada, L.; Cruywagen, E.; de Hoog, G.; Silvera, C.; Najafzadeh, J.; Davison, Elaine; Davison, P.; Barrett, M.; Barrett, R.; Manamgoda, D.; Minnis, A.; Kleczewski, N.; Flory, S.; Castlebury, L.; Clay, K.; Hyde, K.; Maússe-Sitoe, S.; Chen, S.; Lechat, C.; Hairaud, M.; Lesage-Meessen, L.; Pawlowska, J.; Wilk, M.; Sliwinska-Wyrzychowska, A.; Metrak, M.; Wrzosek, M.; Pavlic-Zupanc, D.; Maleme, H.; Slippers, B.; Mac Cormack, W.; Archuby, D.; Grünwald, N.; Tellería, M.; Dueñas, M.; Martín, M.; Marincowitz, S.; de Beer, Z.; Perez, C.; Gené, J.; Marin-Felix, Y.; Groenewald, J. (2013)Novel species of microfungi described in the present study include the following from South Africa: Camarosporium aloes, Phaeococcomyces aloes and Phoma aloes from Aloe, C. psoraleae, Diaporthe psoraleae and D. ...
Dawson, Daniel (2006)Early research into the stable hydrogen isotopic compositions (δD) of petroleum involved bulk deuterium/hydrogen (D/H) measurements which, while providing some useful information, had to contend with the analysis of complex ...
Modelling the co-occurence of Streptococcus pneumoniae with other bacterial and viral pathogens in the upper respiratory tractJacoby, P.; Watson, K.; Bowman, J.; Taylor, A.; Riley, T.; Smith, D.; Lehmann, Deborah (2007)Go to ScienceDirect® Home Skip Main Navigation Links Brought to you by: The University of Western Australia Library Login: + Register Athens/Institution Login Not Registered? - User Name: Password: ...