Chapter 4

Abstract

In this chapter, we summarize recent work on the geologic evolution of the northern Andes. Our intention is to present current information so that scientists from other disciplines can differentiate data from interpretations. In this effort, we focus on thermochronological data that provide precise places, dates, and rates. Thermochronological data provide cooling histories for rocks of the upper crust, whereas provenance data offer insights on rocks that have been eroded away. In reviewing published data, we provide a critical overview of recent paleogeographic interpretations. Specifically, we discuss hypotheses such as (i) Eocene proto-Magdalena River draining toward the Maracaibo Basin, (ii) the presence of a closed proto-Magdalena basin from the late Eocene to middle Miocene, (iii) the Miocene closure of the Isthmus of Panamá, (iv) the late Cenozoic surface uplift of the Eastern Cordillera, and (v) the Cenozoic eastward advance of the Orinoco River. We conclude that in most cases, favored ideas remain as intriguing hypotheses, but there remains room for alternative interpretations. The present summary is intended to provide a cautionary note on the use of limited datasets to make paleogeographic interpretations of the northern Andes.

Topographic response to Neogene variations in slab geometry, climate and drainage reorganization in the Northern Andes of Colombia

“…The hypothesis proposed here challenges the view that the Central Cordillera can be regarded as an old orogen with topography mostly established by the Paleogene (Gómez et al, 2003;Bande et al, 2012;Nie et al, 2012;Villagómez and Spikings, 2013;Mora et al, 2020). We speculate that topography in the southern Cordillera Central is indeed "old" (e.g., Villamizar-Escalante et al, 2021), whereas the topography in the northern Cordillera Central has only been growing since the Late Miocene to Pliocene.…”

“…The Western Cordillera shows a pulse of exhumation at ~40 Ma followed by a decrease in rates (Villagómez and Spikings, 2013). The Neogene topographic evolution of the Western and Central Cordilleras of the Northern Andes remains poorly understood (e.g., Mora et al, 2020). During the Middle Miocene (ca.…”

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

“…On the other hand, several lines of evidence suggest that the modern elevations of the Eastern Cordillera, were only reached during the late Miocene -Pliocene as a consequence of increased crustal shortening (review in Mora et al, 2020). However, sedimentological and thermochronological constraints allowed documenting the presence of isolated uplift events related to an unquantified growing topography since the Paleocene -Eocene, which were likely related to the widening of the northern Andes in response to the shallow subduction of the Caribbean oceanic plateau (Bayona et al, 2020;Parra et al, 2012;and references therein).…”