Epigenetic Mineralization in Yorkshire

Abstract

Summary The lead-zinc-copper-fluorine-barium deposits of N.W. Yorkshire are discordant veins and associated replacements of epigenetic origin. A summary of previous ideas shows that the principle of stratigraphic control has been recognized from earliest times. The structural setting of the deposits on the Rigid Block and their relation to preferred horizons in the Viséan and Namurian rocks is described. After a review of current genetic hypotheses it is suggested that at the time of mineralization, an active circulation of deep groundwaters was augmented by juvenile waters from acidic magmatism in the crust or from still deeper levels. The possible roles of metamorphic and connate waters are considered.