Abstract

The understanding of the interplay between tectonic and magmatic processes is crucial for elucidating the evolution of volcanic systems. The spatio-temporal distribution of volcanic centers can reveal key information concerning eruption dynamics and tectonic processes. Additionally, the distribution and geometry of volcanic alignments provide valuable indicators to assess the tectonic and magmatic influence over time. The Lazufre Volcanic Area (25 to 25°40? S, Southern Central Andes) is characterized by a large-scale elliptical surface deformation pattern that has been associated with magma movement within an overpressured mid-crustal magma reservoir. This volcanic area lies between two main regional fault systems (Archibarca and Culampaja fault zones) and hosts a great number of eruptive centers and several volcanic complexes. Through DEM-based morpho-structural and geomorphological analyses, we examine the morphometric parameters of volcanic alignments with the aim to determine the tectonic or magmatic influence on the spatio-temporal evolution of the volcanic activity in the Lazufre area. We identified 390 volcanic (polygenetic, monogenetic, and parasitic) centers that define 100 volcanic alignments, allowing us to categorize the volcanic evolution into three stages: (1) a Middle Miocene to Lower Pliocene stage, characterized by a high number of volcanic centers and NNW-SSE-oriented volcanic alignments, parallel to sub-parallel to the AFZ and CFZ, indicating a strong tectonic control under a strike-slip tectonic regime; (2) an Upper Pliocene to Middle Pleistocene stage, showing a decrease in volcanic activity with NW–SE-oriented volcanic alignments parallel to the inferred coeval maximum horizontal compressive stress (?Hmax), which can be linked to magmatic overpressure due to the growth of the Lazufre magma reservoir, and to the transition to a transtensive tectonic regime; and (3) an Upper Pleistocene to Holocene stage, characterized by fewer volcanic centers concentrated around the Lastarria-Cerro Bayo complexes, forming NNE-SSW alignments associated with changes in stress field conditions due to the transition to an extensional/strike-slip tectonic regime and the late stages of reservoir growth. Our results indicate that the distribution of volcanism from Neogene to Quaternary in the LVA has been controlled by the interplay between variations in the stress field due to the tectonic evolution of the Central Andes and the magmatic evolution of the Lazufre magma reservoir. © International Association of Volcanology & Chemistry of the Earth's Interior 2025.