CONICET | Buscador de Institutos y Recursos Humanos

Early-middle Miocene alluvial-lacustrine system in the Collón Cura basin and controls on the development of diatomite. The sedimentological and compositional analyzes presented in this contribution allowed inferring the depositional systems and the volcano-sedimentary supply of the early-middle Miocene deposits preserved in the Collón Cura Basin. A volcaniclastic alluvial system laterally related to a lacustrine system with diatomites developed towards the interior of the basin were interpreted. The development of these systems responds to the interaction of tectonic, magmatic and climatic processes occurred in the Andean Patagonian retro arc, such as the initial structural compartmentalization of the foreland, the intermittent and distal pyroclastic supply associated with the arc magmatism, and a temperate sub-humid climate linked to the Miocene Climatic Optimum and the incipient rain shadow effect. This context was conducive to the development of diatomites in the lacustrine system, with volcanic and climatic controls facilitating the contribution of silica and nutrients necessary for their growth.