Imagens sentinel-2a (msi) aplicadas ao mapeamento geológico, Região de Itataia, Santa Quitéria, Ce

Abstract

The phosphorus-uraniferous province of the Itataia region, object of this study, is located in the municipality of Santa Quitéria / CE and inserted in the geological context of Ceará Central Domain (DCC) of the Borborema Province (PB). It is a unique mineralization in the world where Its main ore is colofanite. Satellites equipped with multispectral sensors such as Landsat (TM, ETM +, OLI) series play an important role in geological applications. O The objective of this work was to compare the images of the MSI / Sentinel-2 sensors and the OLI / Landsat-8, using statistical parameters such as Pearson's coefficient, and analyzing its applications for geological mapping. For this, the bands were selected of both sensors and preprocessed to a compatible dataset for Comparation. Subsequently, the coefficients were generated between the pairs of correlated bands, and also band ratios for data analysis. Sentinel-2 images showed strong correlation with Landsat-8 images, with Pearson coefficients ranging from 0.857 to 0.930. With these results confirming the evenness between the sensors. Techniques of Digital Image Processing employed in Sentinel-2A images to enhance the lithologies from the Itataia region were: Band ratios, Optimal Index Factor (OIF), Independent Component Analysis (ICA), Minimum Noise Fraction (MNF), Analysis by Main Components (APC), RGB Composition, and Low Pass Filtering. The compositions RGB colors that best highlighted the lithologies of the study area and enhanced the colofanite (phosphorus-uranium ore) were with MNFs R (3) G (4) B (7) bands and with ICA bands R (6) G (5) B (3). Coupled with powerful PDI techniques, Sentinel-2A images satisfactory results in geological mapping application and mineral prospecting.