Mineral and geochemical characteristics of soils and bottom sediments in the area affected by mining dumps (a case study of the Sibay ore deposit)

Abstract

The article focuses on the chemical composition of hydrosulfates formed in bottom sediments and soils as a consequence of sulfide minerals oxidation in mining waste rock dumps. An alkaline geochemical barrier formed under the dumps reduces pollution of natural-territorial complexes. High concentrations of Zn up to 1.29%, Cu-0.74%, and Cd-27.3 mg/kg are found in the hydrosulfates formed in the river bottom and in the soils. The percentages of exchangeable copper, zinc and cadmium in their total content are 33%, 28% and 22%, respectively. Metals are actively involved in lateral and radial migration, which is regulated by alkaline and evaporation geochemical barriers. The hydrosulfates’ mineralogical composition was studied using microscopy and thermodynamic modeling. Among the secondary minerals, gypsum and iron oxyhydroxides are of primary importance, and to a lesser extent barite, epsomite, and jarosite. Secondary minerals of Cu and Zn in scattering halos are not found, which indicates the leading role of adsorption processes in their phase transitions.

Heavy Metal Pollution and Source Contributions in Agricultural Soils Developed from Karst Landform in the Southwestern Region of China

“…The study area was located in the eastern part of Yunnan Province, where a large number of IOCG-type iron-copper deposits were distributed [ 77 ]. The parent rocks were characterized by rich iron and high copper, which easily cause the enrichment of Cu, Ni and Zn during the development of the soils [ 78 ]. Therefore, factor 4 was a mining activity source.…”

Source analysis and health risk assessment of heavy metals in agricultural land of multi-mineral mining and smelting area in the Karst region – a case study of Jichangpo Town, Southwest China

“…However, because of the intense variation in the grade and thickness, the copper mines currently have no mining value. The soil developed from copper-rich parent rocks is easy to enrich Cu [ 55 ]. Therefore, it can be concluded that Cu in the soil of the study area is affected by the copper mines in the Emeishan basalt.…”