Prospecção geofísica em área de ocorrências de manganês supergênico na região de Heliodora, sul de Minas Gerais

• Autor(a) principal: Reis, Samuel Siqueira [UNESP]
• Data de Publicação: 2015
• Tipo de documento: Trabalho de conclusão de curso
• Idioma: por
• Título da fonte: Repositório Institucional da UNESP
• Texto Completo: http://hdl.handle.net/11449/145443; http://www.athena.biblioteca.unesp.br/exlibris/bd/capelo/2016-10-14/000867835.pdf
• topic: Geofisica; Manganes; Geologia estrutural; Prospecção - Métodos geofísicos; Minas Gerais

This paper discusses the results of combined use of the methods of Electrical Resistivity and Induced Polarization in the geophysical prospection of a supergene manganese mineral occurrence, characterized by manganese and iron oxides with earthy texture, derived from the weathering of spessartite contained in metasediments. From electrical resistivity measurements it was possible to recognize a concentric zone in 2D inversion models, ranging from 73 .m to 380 .m, coinciding with the richer portion in oxides. 2D inversion models for chargeability obtained near the exposed soil profile, helped to determine the entire mineralized zone, characterized by values below 5mV/V. The 3D modeling generated by interpolation of 2D inversion models allowed a morphological analysis of the event, characterized by a wide zone (around 50m) visible on field, but restricted to approximately 10m deep, basically between the horizons B and C of the soil profile. The restriction in depth may be associated with the precipitation of leached metals, in the oxidation-reduction interface provided by the cut in the ground to the road construction, which promotes aeration and soil evapotranspiration. The results reveal the potential of morphological detailing of supergene mineralizations quickly and expeditiously by the combined use of geoelectric methods and data evaluation by 3D modelling