La granodiorita orbicular del Cordón de Lila, región de Antofagasta, Chile

摘要

The orbicular granodioriteof the Cordón de Lila is emplaced within the Ordovician pluton El León, in the southeastern part of Cordón de Lila.This forms a small pipe emplaced in an aplitic band, near the contact with a roof-pendant of amphibole bearing gabbro.The presence of allanite, considered a tracer mineral in magmatic crystallization processes, in the three facies thatconstitute the pipe (core, margin and matrix) suggests that the orbicules of this granodiorite are the result of magmaticcrystallization that affected the magma that originated the orbicular granodiorite.