Mineralogy and geochemistry of trace metals and REE in volcanic massive sulfide host rocks, stream sediments, stream waters and acid mine drainage from the Lousal mine area (Iberian Pyrite Belt, Portugal)

Geochemistry of trace and rare earth elements during weathering of black shale profiles in Northeast Chongqing, Southwestern China: Their mobilization, redistribution, and fractionation

“…The percolating acidic solution can easily carry migrating REEs from the middle section of saprock zone at low pH into the bottom of the saprock zone and fractured shale ( Table 2). The MREEs exhibited depletion pattern in the saprock zone in all three profiles, which is consistent with MREE dissolution and displayed enrichment in solution at lower pH from acidic water/shale interaction experiment (Appendix Table 3 of Supplementary information; Olías et al, 2005;Zhao et al, 2007;Ferreira da Silva et al, 2009). As the percolating solution interacts with shale at middle depths of profiles, H + ion concentrations decrease in the solution, resulting in an increase in the pH value.…”

Hydrothermal alteration in andesitic volcanoes: Trace element redistribution in active and ancient hydrothermal systems of Guadeloupe (Lesser Antilles)

“…Whereas pyrites are notorious for containing all sorts of trace elements, we do not have trace element data in pyrite because they were difficult to separate from the samples. However, according to previous works (e.g., Ece and Nakagawa, 2003;Ferreira da Silva et al, 2009;Gena et al, 2001;Lesher et al, 1986), pyrites associated with hydrothermally-altered andesites are generally depleted in REEs. Therefore, precipitation of S-bearing mineral phases (e.g., gypsum, jarosite, natrojarosite and pyrite) plausibly did not significantly modify the relative concentrations and, thus, abundance ratios of most elements, particularly REEs, in the hydrothermally-altered materials at the GDS volcanic system (Fig.…”

Enrichment of rare earth elements as environmental tracers of contamination by acid mine drainage in salt marshes: A new perspective

“…Johannesson and Lyons, 1995;Verplanck et al, 1999;Gimeno et al, 2000;Gammons et al, 2005;Olías et al, 2005;Ferreira da Silva et al, 2009). The preferential sorptive removal of MREE by precipitation of poorly crystalline iron oxyhydroxides, typical of AMD-affected environments, favors that fluvial sediments also preserve NASCnormalized patterns with convex MREE-signatures (Bau, 1999;Johannesson and Zhou, 1999).…”