Visible-Infrared spectroscopy and chemical properties of water in mining area

Abstract

The present research focuses to investigate the relationship between spectral and chemical characteristics of water samples in Darrehzar mine. In order to reach this aim the chemical characteristics of water were measured through pH, electrical conductivity (EC) and inductively coupled plasma mass spectrometry (ICP-MS) analysis. Furthermore, the visible near infrared (VNIR) and shortwave infrared (SWIR) spectra of water samples were measured by Analytical Spectral Devices (ASD) FieldSpec3 spectroradiometer and the relationships between spectral and chemical characteristics of water samples were calculated. Results of the pH and EC measurements showed that water with high acidity and EC values which indicates presence of acid drainage was located inside the mine. High concentration of copper, sulfur and iron at the samples could be related to copper mineralization and association with acid mine drainage. Results of spectroscopy revealed that second absorption feature (AF2) magnitude correlated significantly with pH (−0.599), EC (0.611) (p < 0.1) and total trace elements plus sulfur (0.822) (p < 0.05). The significant correlation of the AF2 magnitude with concentrations of S (0.854), Pb (0.914), Ni (0.836), Mn (0.834), Co (0.848) and AF3 with concentration of Fe (0.886) confirm that absorption feature magnitude increases by increasing metals concentrations in water.