In the Southern Andean arc, from Jurassic to Pliocene times, repeated periods of compressional and extensional tectonics coupled with subduction-related volcanism give the oppor­tunity to study the relationship between tectonism, magmatism, and sedimentation across a com­posite section between 38° and 39°S. Marine Jurassic formations are associated with calc-alkaline and subordinately alkaline volcanic rocks. The Miocene lacustrine sedimentation was accompanied and mainly ruled by calc-alkaline volcanic activity, which is documented by changes of the detrital composition. The more differentiated volcanism (tholeiitic, calc-alkaline, alkaline) during the Pliocene is related to transtensional tectonics. The stable calc-alkaline component of the Jurassic to Pliocene volcanism confirms a long-term stationary arc segment. This history further suggests that a con­tinuous evolution was modified by multiple source magmatic episodes associated with widening and narrowing in the arc.

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Kemnitz, H.; Kramer, W.; Rosenau, M. (2005): Jurassic to Tertiary tectonic, volcanic, and sedimentary evolution of the Southern Andean intra-arc zone, Chile (38-39°S): a survey. Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen, 236, 1/2, 19-42.