Permian granites in the Pyrenees: the Aya pluton (Basque Country)

Terra Nova, 24, 105–113, 2012 Abstract We show that the Permian volcanism in the Pyrenees was accompanied with emplacement of granite plutons with transitional chemistry. Reassessment of age, structure and petrological characteristics of the Aya pluton, intrusive in the Cinco Villas massif (Basque Country), indicates that it was emplaced at 267.1 ± 1.1 Ma in a dextral transtensive context and that it marks a transition between the high‐K calcalkaline and the alkaline emissions of the first and second Permian volcanic cycles, respectively. This age is close to that of c. 267 Ma reported for lamprophyres dykes of the Pyrenean Axial Zone. These data characterize a period of transition between the Variscan orogeny and the subsequent Alpine cycle in the Pyrenees, with an earlier extensive regime that became widespread in the Pyrenees during the Mesozoic times.