In the department of Cesar, Municipality of Becerril, there are extensive outcroppings of Cretaceous rocks with calcareous sequences belonging to the Lagunitas and Aguas Blancas Formations, the Cogollo Group, and the La Luna Formation. This study presents the mapping of a 25 km2 are in the eastern sector of the Municipality of Becerril, intended to contribute geological knowledge of this area through field work, identification of geomorphological units and petrographic descriptions at a scale 1:25,000. The Lagunitas Formation is characterized by a succession of dark gray massive fossiliferous limestone intercalated with calcareous mudstone and lumachellic limestone. From the Aguas Blancas Formation, the Ánimas Member is identified in detail, consisting of calcareous mudstone with abundant organic matter interbedded with black micritic limestones that grades horizontally to sandstones with fine-grained calcareous cement. The Tucuy Member consists of calcareous siltstone, fine-grained sandstone and carbonated claystone. The Maracas Member consists mainly of massive lumachellic limestone. Similarly, four geomorphological environments were identified: structural, identifying units of hog-backs, homoclinal ridges and cuestas; denudation, identifying units such as erosion scarps, lightly bisected hills and undulating interfluves; karstic, with units of karstic valley and karstic slope; and fluvial, with the floodplain unit.