Some aspects of paleoweathering in the Iberian Hercynian Massif

摘要: Summary The Iberian Hercynian Massif occupies most of the western half Perninsula and forms basement over which Mesozoic, Cenozoic Quaternary materials rest unconformably. Over it can be found remains weathering profiles that are fossilized by marine and/or continental sediments different ages. On southwestern border Tertiary basin Duero below series attributed to lower (Palaeocene), lies a mantle has been displaced effects alpine tectonics. Accordingly, its may appear truncated covered other more recent deposits. present work studies this ancient in zones appears developed slaty province Salamanca, central west Spain. chosen reveal existence strong chemical involves destruction some primary (Fe-bearing chlorites feldspars) formation kaolinites Fe-oxihydroxides. start degradation chlorite occurred during first phases; evolved towards an expandible smectite-like mineral. This phase reflects disappearance albite, analysis points pronounced loss Na. In advanced stage smectites have disappeared, giving way presence kaolinite, goethite hematites. is associated with Mg. main processes occurring these monosiallitisation ferruginisation .