Geoquímica de feldespatos y moscovita de las Pegmatitas del Cap de Creus

Abstract

The Cap de Creus (NE Spain) is the easternmost outcrop of the Hercynian basement of the Pyrenees. The peninsula is constituted by materials affected by the hercynian metamorphism. A pegmatitic field occurs within the metamorphic rocks in the northern part of the Cap de Creus peninsula. Four pegmatite types have been established according to internal structure and mineralogical criteria: microcline-rich (type I); beryl-columbite (type II); beryl-columbite phosphate (type III) and albite (type IV). The composition of moscovite and feldspars have been studied. The K/Rb ratio decreases progressively from type I to type IV, and also there is a progressive enrichment in P, Cs, and Y, according to the degree of pegmatite evolution