Iron’s fingerprint of deposits—iron speciation as a geochemical marker

The article describes the studies of the iron speciation (the occurrence of Fe(II), Fe(III), and complexed iron) in acid leachable fraction of deposits. The speciation of iron was diverse for deposits of different origins and was the specific “fingerprint”—marker of deposition processes. The higher occurrence of Fe(II) may be connected with decantation which has been observed for lake sediments, the majority of Fe(III) with upper flow regime erosion-deposition processes, observed for river sediment deposition during flood episodes. As verification for this hypothesis, the explanation for the iron speciation in the different river sediment samples has been used. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s11356-017-0387-2) contains supplementary material, which is available to authorized users.