How Much Did the Colombian Andes Rise by the Collision of the Caribbean Oceanic Plateau?

Abstract

The quantification of topographic growth at convergent margins is of primary importance to assessing the linkages between tectonic processes and landscape evolution. Traditionally, this task has relied on the applicability of conventional paleobotanical and isotopic methods to estimate paleoelevations, which is not always straightforward. Here, we use recent calibrations based on trace elements of arc‐related magmatic rocks to estimate crustal thickening and surface uplift of the northern Colombian Andes during the early Andean orogeny at ca. 70‐60 Ma. Increased Sr/Y and (La/Yb)N ratios of arc‐related intrusives suggest a ∼20 km crustal thickening that was probably accompanied by an isostatically compensated topographic uplift of up to ∼2 km along the proto‐Central Cordillera and the Santa Marta Range. This kilometer‐scale uplift was coeval with a regional shift from marine to continental deposition in foreland basins and was triggered by the collision of the Caribbean oceanic plateau.

Diverse Magmatic Evolutionary Trends of the Northern Andes Unraveled by Paleocene to Early Eocene Detrital Zircon Geochemistry

“…The 66.0 to 62.0 Ma detrital zircon geochemistry represents the early stages of the arc that followed the Late Cretaceous collision of the Caribbean Plate with the continental margin. This record shows a scenario of limited subduction and magmas that emplaced and differentiated in a thick continental crust (>55 km) that formed during the collision, similar scenarios have been previously suggested (George et al., 2021 and references therein; Leon et al., 2021).…”

“…Whole‐rock geochemistry of Cretaceous magmatic rocks (100 to 80 Ma) supports the existence of a thin to medium (20–55 km) crust before the collision of the Caribbean Plate with the continental margin (Bustamante et al., 2017; Jaramillo et al., 2017; León et al., 2021). Detrital zircons of Cretaceous age (101.9 to 66.2 Ma) retrieved from the Bogotá Formation agree with this scenario: their low Eu anomalies (Eu/Eu*) are consistent with a medium crust and provide thickness estimates of 44 ± 8 km (Figure S4 in Supporting Information .…”

“…This Late Cretaceous‐Paleocene collisional orogenic phase resulted in the development of high topography that became the source area of adjacent syn‐orogenic basins to the east (Bayona et al., 2021; León et al., 2021; Pardo‐Trujillo et al., 2020; Zapata et al., 2021). The syn‐orogenic middle Paleocene‐early Eocene continental succession of the Bogotá Formation (61‐50 Ma) corresponds to a fluvial system that accumulated under high subsidence rates in a basin adjacent to the PECMA (Figure 1a) (Bayona et al., 2012, 2021).…”

Peer Review #4 of "Synthesis of geological data and comparative phylogeography of lowland tetrapods suggests recent dispersal through lowland portals crossing the Eastern Andean Cordillera (v0.2)"

“…Near the end of the Cretaceous (~66 Ma), oceanic-borne terranes collided with the Cretaceous passive margin of northwestern South America (Weber et al, 2009;Cardona et al, 2012;Montes et al, 2019). Arc-continent collisions built ~2 km of relief along the margin of northwestern South America (León et al, 2021), shedding coarse-grained sand and gravel eastwards, forcing a regional marine regression where swampy conditions were established instead (Villamil, 1999;Gómez et al, 2003). A primordial, probably discontinuous, CC rose from Guayaquil to the Guajira peninsula, taking ~10 Ma to propagate from south to north, spawning the first Amazonian/Orinoco-style drainages, perhaps shutting down most or all westward-directed drainages of the region (Hoorn et al, 2010;Horton et al, 2010;Hurtado et al, 2018).…”

Synthesis of geological data and comparative phylogeography of lowland tetrapods suggests recent dispersal through lowland portals crossing the Eastern Andean Cordillera

“…Near the end of the Cretaceous (~66 Ma), oceanic-borne terranes collided with the Cretaceous passive margin of northwestern South America ( Weber et al, 2009 ; Cardona et al, 2012 ; Montes et al, 2019 ). Arc-continent collisions built ~2 km of relief along the margin of northwestern South America ( León, Monsalve & Bustamante, 2021 ), shedding coarse-grained sand and gravel eastwards, forcing a regional marine regression where swampy conditions were established instead ( Villamil, 1999 ; Gómez et al, 2003 ). A primordial, probably discontinuous, CC rose from Guayaquil to the Guajira peninsula, taking ~10 Ma to propagate from south to north, spawning the first Amazonian/Orinoco-style drainages, perhaps shutting down most or all westward-directed drainages of the region ( Hoorn et al, 2010 ; Horton et al, 2010 ; Hurtado et al, 2018 ).…”