Jurassic and Lower Cretaceous magmatic activity in the present-day Coastal Cordillera and the Central Depression of northern Chile is marked by important plutonic and volcanic cycles. The Initial Basics unit of the Coloso Coastal gabbro complex contains the first intrusives into an ensialic marginal basin related to extension, probably due to strike-slip plate motion. These gabbros have affinities with continental tholeiitic basalts. The subsequent Jurassic Volcanic unit, ranging from basalt to andesite in composition, erupted onto the subsiding basin. Simultaneous with and after the eruption of the Volcanic unit, the Late Granitoids unit was intruded. The earliest intrusives of this Late Granitoid unit (GI of the Coastal Cordillera) follow the Initial Basics in time and have similar geochemical source indicators. Geochemical signatures of both the Volcanic unit and the Late Granitoid intrusives suggest that they are related to contemporaneous subduction. Some Late Granitoids (GII of the Central Depression) show evidence of significant crustal contamination much like that of modern Andean magmatism.