A radiometric and petrographic interpretation of discrepancies on uranium content in samples collected at Alte Madonie Mounts region (Sicily, Italy)

The average values of concentrations of 226Ra, 228Ac and 40K were respectively 30, 17 and 227 Bq kg−1 while the greatest values were 134, 59 and 748 Bq kg−1. Linear relationships were observed between 226Ra, 228Ac and 40K concentrations: the activities of 226Ra and 228Ac were comparable, while those of 40K were about 10 times greater. An exception was highlighted for a group of samples where 226Ra activities were much higher than expectations. Chemical compositions and mineralogical features of the samples have made it possible to justify these anomalies.