Early Andean subduction in the Jurassic formed a volcanic arc in northern Chile known as La Negra Arc. The remnants of this arc are now exposed in the Chilean Coast Range. Several plutons were emplaced in the Chilean Coast Range in the Jurassic and Early Cretaceous including the Vicuña Mackenna Batholith.Charrier et al. 2006, pp. 47–48. Further east at similar latitudes, in Argentina and Bolivia, the Salta rift system developed during the Late Jurassic and the Early Cretaceous. Salar de Atacama Basin, which is thought to be the western arm of the rift system, accumulated during the Late Cretaceous and Early Paleogene a >6,000 m thick pile of sediments now known as the Purilactis Group.
