The sites were encountered on top of areas characterized by hydrothermal activity as geysers and other vents, suggesting a preferred location for the incubation of the dinosaur eggs.

Rusconi (1936), Bordas (1941), Pascual (1954), Guiñazú (1962) and Zuzek (1978) assigned a Miocene age to the formation, based on mammal fossils found in the strata.

[5] The occurrence of typical Cretaceous charophytes confirms the assigned age for Los Llanos Formation.

[8] It comprises lightgrey and orange sandstones with basal conglomerate beds,[8] deposited in a fluvial environment, which in the Sanagasta park is associated with hydrothermal activity.

[9] The more than 90 sauropod nests were found in direct association with these hydrothermal vents, suggesting a preferred incubation location of the mother dinosaurs.