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Abstract We use new and published detrital zircon U‐Pb data (n > 10,000) from Oligocene‐Pliocene strata of intermontane basins of the western Colombian Andes and surrounding regions to study the evolution of sedimentary systems during the transition from arc collision/accretion to subduction. Our database indicates a shift from a compartmentalized basin architecture, locally fed by transverse drainages, toward one with enhanced connectivity and longitudinal sediment dispersal during the Middle‐Late Miocene. These events were accompanied by the end of local marine influence on depocenters and the progressive uplift of the flanking Colombian Cordilleras as they became continuous topographic features. Post‐Pliocene local and transient disruption of longitudinal rivers was caused by damming and valley‐filling, attributed to volcaniclastic flows. We interpret the inherent segmentation of strike‐slip faults and their morphological expressions as the primary controls on depocenter evolution during Early‐Middle Miocene arc collision/accretion. The subsequent transition to subduction and the tectonic segmentation of the continental margin triggered asymmetrical basin inversion in the western Colombian Andes. The modern rugged morphology in the northern intermontane region is arguably associated with widespread uplift due to upper plate cooling and strengthening by shallow subduction of the Coiba microplate. Conversely, the wide and flat morphology of aggradational basins in the southern intermontane area is interpreted as the result of incomplete inversion and the dominance of strike‐slip tectonics. The “normal” subduction of the Malpelo microplate beneath southern Colombia might be linked to a higher heat flow and localized deformation in the intra‐ and back‐arc regions. 

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. 

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.