A second phase of compressive margin has been noted in the Cesar-Ranchería Basin by the strong differences between the sedimentary thicknesses of the Paleocene formations. During this stage in the basin development, the Cesar-Ranchería Basin was connected to the Middle Magdalena Valley to the west. The Paleocene Lisama Formation has a reduced thickness in the northern part of the Middle Magdalena Valley due to erosion, while the Paleocene section in the Cesar-Ranchería Basin is very thick. This has been explained by the tilt of the Sierra Nevada de Santa Marta and the formation of several thick-skinned thrust faults in the basin. The initiation of this compressive phase has been dated to the Maastrichtian, when tectonic uplift and deformation was active in the Central Ranges, to the west of the basin.