Genesis of the three concentrically-zoned granitoid Plutons of Cauterets-Panticosa (French and Spanish Western Pyrenees)

Abstract

The petrogenesis of the Hercynian plutons of Cauterets-Panticosa was deduced from detailed cartographic, petrographic, chemical (> 300 analyses) and mineralogical evidence. The three adjacent calc-alkaline plutons were derived from a siliceous continental magma modified to varying degrees by hybridization with a mafic mantle-derived magma. The mafic inclusions are evidence for the mafic parent magma. Each of the three plutons is made up of several more or less concentrically disposed granitoid units. This concentric zonation is either recurrent (West Cauterets Pluton), or normal (Panticosa Pluton), or both normal and recurrent (East Cauterets Pluton). The combination of several processes (hybridization, differentiation, multiple intrusion, subterranean collapse) was responsible for the genesis of the three plutons.