Occurrence and distribution of high arsenic in sediments and groundwater of the Claromecó fluvial basin, southern Pampean plain (Argentina).

Occurrences of high arsenic (As) in sediments and groundwaters were investigated in the Claromecó fluvial basin, southern Pampean plain, Argentina. This investigation includes sedimentology, mineralogy, and hydrogeochemistry of the Neogene and Quaternary aquifers to determine possible sources and transport mechanisms for As in the Claromecó basin. Characterization of the sediments revealed homogeneous mineralogy in both Neogene highlands and Quaternary floodplains with abundant plagioclase, volcanic glass shards (VGS), K-feldspar, quartz, clay minerals and minor concentrations of clinopyroxenes, orthopyroxenes, hornblende, epidote, Fe-(oxy)hydroxides and fluorapatite.