Estructuras elípticas en el plutón de la Sierra del Francés: estudio de su geometría e hipótesis sobre su origen convectivo

Abstract

Direct evidences or magmatic convective flow in granitic pluton are scarce. The possible complex history of magma cooling in pluton can delele partially or completely this registration. We describe a complex elliptical structure in a porphyritic monzogranite and the granitic fabric around this. We distinguish three zones based on the study of their morphology and internal Structures (cross-cutting layering, curved schlierens, lobulated mafic-leucocratic laminate). We propose a model of verticall flow pipes with motion or magma generation point. Three possible convective build the elliptical structure. This model is similar those proposed in the literature for snail and ladder dike structures. Fabric defined by K-feldspars megacryst in the inmediatelly surrounding is basically linear to 355·010º