@InProceedings{NaletoPerrSouz:2017:EsAsRe,
               author = "Naleto, Jo{\~a}o Lu{\'{\i}}s Carneiro and Perrotta, Monica 
                         Mazzini and Souza Filho, Carlos Roberto",
                title = "Estudo de assinaturas de reflect{\^a}ncia de amostras de rocha do 
                         dep{\'o}sito de Au de Pedra Branca, regi{\~a}o da Serra das 
                         Pipocas, CE",
            booktitle = "Anais...",
                 year = "2017",
               editor = "Gherardi, Douglas Francisco Marcolino and Arag{\~a}o, Luiz 
                         Eduardo Oliveira e Cruz de",
                pages = "7316--7322",
         organization = "Simp{\'o}sio Brasileiro de Sensoriamento Remoto, 18. (SBSR)",
            publisher = "Instituto Nacional de Pesquisas Espaciais (INPE)",
              address = "S{\~a}o Jos{\'e} dos Campos",
             abstract = "The Geological Survey of Brazil (CPRM) has been investigating the 
                         mineral resources potential of the Troia Massif, which is an 
                         Archean/Paleoproterozoic nucleus located at the central region of 
                         Cear{\'a} State. In this area, gold mineralization hosted by 
                         metavolcano-sedimentary sequences has been recently discovered by 
                         private exploration projects (Pedra Branca deposit). The gold is 
                         associated to quartz veins and hydrothermal alteration, hosted by 
                         amphibolites, metandesites, metatonalites and metasedimentary 
                         rocks, placed along a main NE-SW regional structure. In this 
                         context, a set of rock samples from the area were collected in 
                         order to study their compositional and physicochemical variations 
                         related to the hydrothermal alteration, through the extraction and 
                         analysis of their reflectance spectral signatures. The spectra of 
                         altered and fresh rocks samples were measured with an ASD 
                         FieldSpec-3 High-Resolution spectroradiometer and the 
                         mineralogical interpretations were performed visually, based on 
                         the GMEX and USGS reference spectral libraries. The results show a 
                         hydrothermal zonation consistent with orogenic gold deposits 
                         hosted by greenstone belts, defined by four main mineral 
                         assemblages: (i) amphiboles + biotite + epidote + Mg-chlorite 
                         (unaltered), (ii) FeMg-chlorite + calcite + paragonite (distal, 
                         chlorite zone), (iii) ankerite/siderite + muscovite + calcite + 
                         FeMg-chlorite (intermediate, carbonate zone), (iv) phengite + 
                         ankerite/siderite (proximal, muscovite zone). The mineralogical 
                         model proposed is coherent with the geological and metallogenetic 
                         patterns defined by previous studies, which indicates its 
                         feasibility in prospecting new Au deposits in the region.",
  conference-location = "Santos",
      conference-year = "28-31 maio 2017",
                 isbn = "978-85-17-00088-1",
                label = "60049",
             language = "pt",
         organisation = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                  ibi = "8JMKD3MGP6W34M/3PSMFFR",
                  url = "http://urlib.net/ibi/8JMKD3MGP6W34M/3PSMFFR",
           targetfile = "60049.pdf",
                 type = "Geologia",
        urlaccessdate = "27 abr. 2024"
}