Modelagem geológica e geoestatística de recursos minerais: mina de medrado - Andorinhas/Ba

Abstract

In Brazil, there is a wide variety of mineral deposits, among which the chromitiferous deposits of the Jucurici Valley in the municipality of Andorinhas/BA stand out. Within the complex, the Ipueira-Medrado mine segment constitutes two of the main chrome mines in the country. Therefore, the main objective of the work is a new analysis of the Medrado mine, integrating geochemical, lithological data, digital image processing, aerogeophysics and geostatistical analysis of the area for the reassessment of the deposit and creation of 3D digital models. The data used comes from different sources: geochemistry and lithology of the mineral deposit (provided by Ferbasa); radiometric and magnetic aerogeophysics data (provided by CBPM); and optical and radar images from remote sensing (acquired from the USGS website). The methodology used in this work involves the integration of several data processing techniques in order to develop three- dimensional geological models in a 3D environment, using the Studio RM platform. To achieve this end, data from aerogeophysics and remote sensing were used to map the geological bodies present on the surface, providing a solid basis for the development of these models. The process of creating mathematical models followed a classical approach, involving the sequential construction of points, lines and surfaces. Furthermore, experimental variograms were developed, and geostatistical analyzes were performed, using algorithms such as Ordinary Kriging and Nearest Neighbor. These steps aimed to create geostatistical models and compare the results obtained with more traditional modeling approaches, such as classic cubage. At the end of this process, through the geological model of the Medrado mine, it was possible to obtain a deeper understanding of the structure of the chromititic bodies in the Jacurici Valley, thus bringing valuable knowledge to the geoscientific context.