Abstract

The space-time analysis of the evolution of Cretaceous-Paleogene magmatism by Díaz-Bravo et al. (2022), identifies the development of a continuous magmatic arc along the continental margin, contradicting the migration of the arc towards the continent as a consequence of flattening of the Farallon plate (Damon et al., 1981). This magmatism was developed simultaneously in the interior of the continent and interrupted during the Paleocene. Consequently, our conclusions are not an adaptation of magmatic ages in the context of planar subduction as suggested by Chávez-Cabello and Ramírez-Peña (2023). Including U–Pb ages from a few missing Cretaceous plutons in our analysis do not change our model at all but enrich it.The study of regional deformation was not part of the objectives of our work, but we pointed out some issues about the temporality of magmatism and deformation previously documented, trying to prevent future misinterpretations. We show here that magmatism was emplaced at the beginning and end of the Late Cretaceous deformation phase of the Mexican Fold and Thrust Belt, and it was absent during the Paleocene-Eocene deformation stage. We ruled out tectonic transport of the Cretaceous plutons, or we think that it should be negligible considering how far (hundreds of kilometers) are these and other plutons from the paleo-trench. Furthermore, plutons such as Pico de Teyra were not located in the thin-skinned cover and others such as El Milagro and La Pólvora do not present deformation features. A large syn-tectonic displacement scenario should be changed dramatically the texture of these rocks, but large parts of these plutons preserve magmatic textures and some of them do not show evidence of deformation. Also, is very likely that the P-T conditions in such large transportation, would induce recrystallization and resetting of some isotopic systems (i. e., K–Ar) but it is not observed or has not been documented. We highlight the contributions we have made to the knowledge of the intracontinental plutons studied and the adequate documentation of our work. Finally, we insist that pre-Mesozoic basement is little known in the study area, despite the documented geophysical data.

Full Text
Published version (Free)

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call