Structural and mineralochemical characterization of a pegmatite deposit in the Santa Rosa Pegmatite Field, Minas Gerais Brazil

• Autor(a) principal: Joncew,Henrique Chaves
• Data de Publicação: 2019
• Outros Autores: Aranha,Paulo Roberto Antunes, Horn,Adolf Heinrch
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: REM - International Engineering Journal
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S2448-167X2019000400425
• topic: Pegmatite; prospecting; GPR; geochemistry; modeling

Abstract The Santa Rosa Pegmatite Field (SRPF), in northeastern Minas Gerais State, is one of the most important gemstone sources in Brazil. The economy of several neighboring cities greatly relies on the trade of its gemstones. However, efforts to improve gemstone mining with practical, scientific methods are scarce, making it a yet inexpensive, marginally profitable practice. In this scenario, it is opportune to encourage new approaches to optimize mining in pegmatitic deposits. This study looked into the case of a tourmaline dig in the city of Franciscópolis, near Teófilo Otoni. The pegmatite has a weakly zoned structure, and was formed during the final stages of the Neoproterozoic Araçuaí Orogeny, associated with the intrusion and crystallization of the Santa Rosa Granite. GPR profiles were executed to locate structural anomalies inside the rock and its contacts with the host rock, and mineral samples were characterized based on compositional data obtained from ICP-MS and microprobe analyses. The results provided useful information that enabled the creation of a tridimensional digital model of the dig and the pegmatite dike, and may guide future operations in the dig. In the future, the proposed methodology may be applied to more cases to generate a database of geological information that, in addition to the economic scope, could lead to a better understanding of the local granite-pegmatite systems.