The article presents the results of preliminary geochemical and mineralogical studies of technogenic soils (Technosols) of abandoned iron ore mines on the Ławęczna Hill near Miedziana Góra in the Holy Cross (Świętokrzyskie) Mountains, southcentral Poland. The results of chemical analyses (XRF) were used to calculate the soil enrichment factors of arsenic, copper, iron, lead and zinc, and compare the element concentrations to their levels in uncontaminated soils across Poland and in the city of Kielce. The highest values of soil enrichment factors of metals (As 27.699, Ni 26.455, Cu 9.353, Zn 3.344, Pb 0.62) were recorded for the sand fraction composed of iron oxyhydroxides and hematite, whereas the lowest (Ni 0.22, Cu 0.069, Zn 0.007, Pb 0.028) for the clay–silt and sand fractions, which were primarily composed of calcite and quartz as well as for gravel fraction. The clay-silt fraction shows the highest enrichment in arsenic (27.69). The examined metals and arsenic show positive geochemical anomalies.
As so ci ate ed i tor: Tomasz Bajda The min er al og i cal and geo chem i cal char ac ter is tics of cala mines de vel oped from chem i cal weath er ing within two dif fer ent tec tonic set tings (tec tonic horst and graben) are de scribed. Cala mines col lected from the Olkusz-Pomorzany and the Boles³aw zinc and lead mines were ana lysed geochemically by means of EMP and SEM-EDS and their min er al og i cal compo si tion was iden ti fied by us ing re flected light mi cros copy and XRD anal y sis. The cala mines from the Olkusz-Pomorzany mine are com posed of marcasite, ga lena, cerussite, sphalerite, hemimorphite, smithsonite and goethite. Hemimorphite prevails over smithsonite and oc curs in the vi cin ity of pri mary sulphides. The min er al og i cal com po si tion of the cala mines from the Boles³aw area is less di verse. These are pri mar ily com posed of goethite and smithsonite, with a mi nor con tent of marcasite and rem nant sphalerite. The min eral com po si tion of weath er ing sites in the Olkusz-Pomorzany and Boles³aw areas may re flect dif fer ent geo chem i cal con di tions (from slightly acidic to al ka line pH val ues, from lower to higher CO 2 par tial pres sure and so lu tions of dif fer ent sil ica sat u ra tion) that could have changed over time. The min er al og i cal com po si tions of the cala mines dif fer quan ti ta tively and this could re flect the tec tonic set ting of the pri mary ore af fect ing the rate of chem i cal weath er ing.
<p>Study area is located in the Olkusz ore district, in the south Poland where Zn and Pb were recovered from sulfide and calamine ore bodies. The primary ore is composed mainly of sphalerite, galena, and marcasite/pyrite and was excavated from the so-called ore bearing dolomite of the Middle Triassic age. Studied rocks are mainly composed of smithsonite, cerussite, goethite, hemimorphite, anglesite and are considered as supergene ore derived from alterations of sulfides mainly during Miocene. The chemically-mediated weathering of sulfides has extensively been studied, whereas microbially-mediated weathering of calamines requires experimental research to be undertaken to improve our understanding on dissolution of such rocks. This study aimed: (i) to determine the bioleaching potential of Zn, Pb, Cd, and As from Zn-bearing supergene ores exposed to <em>A. thiooxidans</em>, native soil microorganisms, and root exudates; (ii) to assess the impact of mineral composition (goethite-bearing vs. hemimorphite-bearing samples) of the rocks on leaching of elements; (iii) to determine mineral dissolution under bioweathering conditions. Two supergene samples were investigated: first collected from the mining heap next to the abandoned &#8220;Boles&#322;aw&#8221; calamine open-pit in the Boles&#322;aw village (B), and second from the weathering site of the abandoned &#8220;Olkusz-Pomorzany&#8221; Zn-Pb underground mine (OP). Trace elements in solutions were measured using by ICP-QQQ whereas mineral composition of the fresh and weathered samples was determined using by XRD, SEM-EDS, EPMA, and DSC-TG methods. Results of the experiments revealed the highest leaching efficiency for Zn was found for both samples treated by <em>A. thiooxidans</em>&#160; (up to 125&#160;000 and 14&#160;000 mg&#183;kg<sup>-1 </sup>for OP and B, respectively) and Cd (up to 817 and 46.8 mg&#183;kg<sup>-1 </sup>for OP and B, respectively). The highest amounts of Pb (3840 mg&#183;kg<sup>-1 </sup>&#160;and 660 mg&#183;kg<sup>-1</sup>) were liberated from sample OP by root exudates and soil bacteria, respectively. As compared to other elements studied, arsenic revealed the lowest leaching efficiency under bioweathering conditions. In sample OP, dissolution of hemimorphite and cerussite caused the release of Zn and Pb, respectively. In sample B, goethite was found to weather intensively.</p>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.