clay and fluorapatite

In central India, fluoride contamination in deeper basaltic aquifer is geogenic. This study demonstrates the source of fluorine enrichment in aquifer matrix and its release mechanism into groundwater. Magmatic-hydrothermal residual melt, i.e., albitic-calcic-amphibole-apatite-rich intrusive rock is the main source of fluorine enrichment. The association of this rock with interflow carbonate-clay assemblage played a significant role for fluoride contamination. Fluorine-enriched residual melt interacted with interflow carbonate-clay association, and this interaction metasomatized the carbonates and enhanced fluorine concentration in sediments. Bulk fluorine concentration of 988 ppm is measured in the soil developed over the association of intrusive rock and carbonate-clay assemblage. X-ray diffraction and electron-probe micro analysis confirmed the presence of fluorine-bearing and/or containing minerals, i.e., fluorite, fluorapatite, and palygorskite. The presence of bicarbonate and Na

Topics: Bicarbonates; Clay; Environmental Monitoring; Fluorides; Fluorine; Groundwater; India; Water Pollutants, Chemical