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Abstract The northern Andes of southern Colombia contain a rich geologic history recorded by Proterozoic to Cenozoic metamorphic, igneous, and sedimentary rocks. The region plays a pivotal role in understanding the evolution of topography in northwestern South America and the development of large river systems, such as the Amazon, Orinoco, and Magdalena rivers. However, understanding of the basement framework has been hindered by challenging access, security concerns, tropical climate, and outcrop scarcity. Further, an insufficient geochronologic characterization of Andean basement complicates provenance interpretations of adjacent basins and restricts understanding of the paleogeographic evolution of southern Colombia. To address these issues, this paper presents a zircon U-Pb geochronological dataset derived for 24 bedrock samples and 19 modern river samples. The zircon U-Pb results reveal that the Eastern Cordillera of southern Colombia is underlain by basement rocks that originated in various tectonic events since ca. 1.5 Ga, including the accretion of discrete terranes. The oldest rocks, found in the Garzon Massif, are high-grade metamorphic rocks with contrasting Proterozoic protolith crystallization ages. Whereas the SW part of the massif formed during the Putumayo Orogeny (ca. 1.2–0.9 Ga), we report orthogneisses for the NE segment with protoliths formed at ca. 1.5 Ga, representing the NW continuation of the Rio Negro Jurena province of the Amazonian Craton. In contrast, crystalline rocks of the Central Cordillera primarily consist of Permian–Triassic (ca. 270–250 Ma) and Jurassic–Cretaceous (ca. 180–130 Ma) igneous rocks formed in a magmatic arc. In southernmost Colombia, the Putumayo Mountains mainly consist of Jurassic–Cretaceous (180–130 Ma) plutonic and volcanic rocks. Furthermore, we analyzed the heavy mineral abundances in modern river sands in southern Colombia (spanning 1°N–5°N) and found that key minerals such as garnet and epidote can be utilized to trace high-grade metamorphic and igneous lithologies, respectively, in the river catchments. The differentiation of basement ages for separate tectonic provinces, combined with heavy mineral abundances in modern sands, can serve as unique fingerprints in provenance analyses to trace the topographic and exhumational evolution of different Andean regions through time. 

ABSTRACT The topographic growth of the Eastern Cordillera in the northern Andes of Colombia is a critical event in the tectonic and paleogeographic evolution of the western Amazon Basin. Documentation of early orogenic growth is enabled through multi‐proxy provenance signatures recorded in the adjacent retro‐foreland basin. In broken foreland basins, basement highs interrupt the lateral continuity of facies belts and potentially mask provenance signals. The Putumayo Basin is a broken foreland basin in western Amazonia at ~1°–3° N, where the Florencia, Macarena, and El Melón‐Vaupes basement highs have compartmentalised discrete depocentres during basin development. This study presents new evidence from stratigraphic, conglomerate clast count, sandstone petrography, detrital zircon U–Pb geochronology and novel apatite detrital U–Pb age trace element geochemistry analyses. The results show that the southern Eastern Cordillera (i.e., Garzon Massif) and Putumayo Basin basement highs were initially uplifted during the Late Cretaceous coeval with the Central Cordillera, most likely associated with the collision of the Caribbean Large Igneous Province (CLIP). Distinctive facies distributions and provenance changes characterise the Putumayo Basin over a ~300 km distance from south to north, in the Rumiyaco Formation and Neme Sandstone. Detrital zircon U–Pb ages record a sharp reversal from easterly derived Proterozoic to westerly sourced late Mesozoic–Cenozoic Andean zircons derived principally from the Central Cordillera. Provenance signatures of the synorogenic Eocene Pepino Formation demonstrate the continued exhumation of the Eastern Cordillera as a second‐order source area. However, the emergence of the northern intraplate highs modulated the provenance signature due to the rapid unroofing of relatively thinner marine sedimentary cover strata that overlie the Putumayo basement, in comparison to the thicker sequences of the southern basin. The provenance data and facies distributions of the Oligocene–Miocene Orito Group were more heterogeneous due to strike‐slip deformation, associated with major plate tectonic reorganisation as the Nazca Plate subducted under the South American margin. 

The eastern foothills in the Colombian Eastern Cordillera have been an important oil-producing region since the discovery of the Cupiagua and Cusiana fields. Three organic-rich units are considered to be the main source rocks. The Aptian Fómeque and the Cenomanian-Coniacian Chipaque Formations comprise a siliciclastic to locally carbonate shallow marine shelf succession with type-II kerogen, whereas the Paleocene Los Cuervos Formation consists of marginal marine to nonmarine siliciclastic rocks with type-III kerogen. We modeled the petroleum systems of these three source units to characterize the hydrocarbon generation-accumulation processes within the basin. The structural record of the Eastern Cordillera shows that the most important tectonic event began in early Oligocene with contractional deformation along the Soapaga through Guaicaramo faults during early Miocene, culminating during the Pliocene with the Cusiana and Yopal faults. These variable rates of burial and exhumation resulted in contrasting time-temperature histories for each of the source rocks. The Fómeque Formation reached the oil window during the Paleocene in the south and the Eocene to the north. In contrast, the Chipaque Formation generation started during Early Oligocene in the south and by Late Oligocene to the north. Conversely, maturation for the Los Cuervos Formation was uniform along the foothills, reaching the oil window during Late Oligocene. Charge history modeling suggested that the Albian sandstones reservoirs were filled between Oligocene to Miocene. In contrast, the proven reservoirs in the area (the Upper Cretaceous, Paleocene, and Eocene sandstones) were filled by late Miocene, with a second episode of recent charge in the Eocene reservoirs, and perhaps active, from the Los Cuervos Formation. The results of this work proved that petroleum system modeling is useful not only to characterize generation-migration processes but it also can be used as a prediction tool in structurally complex areas such as the Colombian foothills.