The distribution of iodine and chlorine in soils over lead-zinc mineralisation, East of Glogfawr, mid-Wales

The potential pathfinder elements iodine, as total (I_tot) and watersoluble (I_aq), chlorine (Cl_tot and Cl_aq) together with F, As, Pb, Zn and Cu have been determined in B horizon soils over proved lead-zinc mineralisation east of the disused Glogfawr mine, Dyfed, Wales. Pb and Cu are anomalous in soils over this occurrence while Zn fails to reflect underlying mineralisation. Total and water soluble I and Cl show anomalously high values over the proved mineralisation and also indicate extensions along the trend of the mineralised fracture system to the south-southwest and the north-northeast; these anomalies are more extensive than those formed by Pb or Cu. In the soils analysed there is a strong correlation between I_tot and I_aq and Cl_tot and Cl_aq and it is possible that a simple water-extractable method could be of use in geochemical prospecting.