Spatiotemporal variability of magmatic products under a changing structural and tectonic context: a case study in the Andes of southern Central Chile

In a subduction setting, the type of magmatic products which reach upper crust, and eventually surface, depends on several variables, among some most relevant are tectonic regime, orientation magma pathways relative to predominant stress tensor. To better understand this relationship, we studied in detail an area Andes southern Central Chile subduction-related magmatism has been active at least during last 18 m.y. The relationship between high-angle faults was studied, spatiotemporal variations tensor were analyzed. chemistry different used evaluate “fertility”, understood as its potential form giant porphyry-type deposit. age units is constrained by new U-Pb zircon ages, complemented with previous geochronological studies. Three main fault systems present: ∼NW striking structures control emplacement plutonic bodies, while ∼NE–ENE N–NNE faults, more parallel prevailing σ 1 since middle Miocene, dike swarms volcanic alignments. Regarding geochemical characterization, transition towards steeper REE patterns higher fertility indices observed earliest facies La Invernada Plutonic Complex (∼15-14 Ma), coincident Miocene orogenic event described latitude authors. Pliocene Resolana intrusions show indices; however, they still considerably lower than those typical for porphyry-forming magmas same Andean region. It concluded that contrasting coeval emplaced under context, cannot be explained continental-scale processes; instead, related differences local ascent through crust. Fault miss-oriented appear favor longer residence times, achieving degree differentiation cases crystalizing within ascending favorably oriented primitive, often surface forming stratovolcanoes alignments monogenetic vents.