Por: William Martínez Valladares y Alonso Arturo Marchena Campos, Instituto Geológico, Minero y Metalúrgico (Ingemmet).

Abstract

The Incapuquio fault system is an important structural control that hosts the most important Paleocene age porphyries of southern Peru (such as Cuajone and Toquepala). In the Oligo-Miocene era, this structural control hosted again porphyritic systems (Chipispaya porphyry). 

The lithogeochemistry of magmas responsible for generating hydrothermal systems during their last stages of differentiation in higher cortical levels is intimately linked to the geotectonic context in which their magmatic-hydrothermal evolution developed. The major elements allow the characterization of magmatic series in regional geotectonic contexts (for example, calcoalkaline series in the context of subduction tectonics). 

The magmatism of the porphyritic system, given its local nature, is best characterized using lithogeochemistry of trace elements, which are especially useful in identifying variables of petrogenetic significance during the evolution of magmatism. Therefore, through lithogeochemical parameters of trace elements we can distinguish the lithogeochemical differences between magmatism linked to porphyries and magmatism of the respective regional magmatic arch that hosts it. This porphyry-linked magmatism reflects in its lithogeochemical parameters anomalous values in comparison to regional magmatism, such as high La/Yb, Sr/Y, Eu/Eu* values, indicators of favorable conditions for the generation of fertile magmas.