Utilizing lineaments extracted from radar Images and drainage network to evaluate the mineral potential of Au and Cu in the Bom Jardim Group (Neoproterozoic), Southern Brazil

Abstract

The exploration of gold and copper is essential for the sustainable development of mining worldwide and in Brazil, given the dependency on copper imports. This study aims to reassess and identify promising areas for sulfide prospecting in southern Brazil, with technologies, including radar images (ALOS PALSAR) and software (PCI Geomatics CATALYST Professional Complete, version 2023, QGIS 3.38.1 (Grenoble), Spring 5.5.6, and Orient 3.20.0), for the extraction and processing of tectonic lineaments. The comparative analysis between these linear structures and the drainage networks allows for the assessment of alluvial gold minerals and disseminated copper in andesites, as observed in the abandoned Seival mines. The methods employed include the extraction of tectonic lineaments and the evaluation of mineral occurrences in the Hilário (volcanogenic) and Arroio dos Nobres (sedimentary) formations of the Bom Jardim Group (Neoproterozoic) and their drainage networks. As a result, this article concludes that the main tectonic alignment directions for copper and gold occurrences disseminated in andesites are predominantly E–W, N–S, N 5◦ W, N 58◦ W, N 62◦ E, and N 23◦ E, and for alluvial gold N–S and N 45◦ W. These results are crucial for reassessing abandoned mining areas and identifying the primary mineral orientations in rocks and the predominant orientation of alluvial deposits, serving as structural controls for discovering new mineral occurrences. It is concluded that geotechnologies have expanded the possibilities for study, enabling a more detailed analysis of tectonic lineaments and drainage systems and providing a valuable prospective guide for gold and copper mineral exploration.