Comment on: Geochronology and geothermometry of the Laramide metamorphism in the Cambrian metabasalts from the Cerro Rajon Formation, Caborca region, northwest Mexico by A. J. Barron-Diaz, F. A. Paz-Moreno, D. P. Miggins and A. Iriondo

In their paper, Barron-Diaz et al. (2019a) present new geochronological and thermobarometric data of rocks of the Bamori Ranch area, Caborca region, Sonora, Mexico. The authors interpret the greenschist facies of Neoproterozoic and Paleozoic strata as a result of contact metamorphism close to supposed extended granodioritic intrusions that emplaced during Laramide time (90-40 Ma). In our opinion, this interpretation is poorly constrained. Based on previous geological studies as well as a re-evaluation of presented thermobarometric data, we propose that greenschist facies metamorphism and 40Ar-39Ar ages described by the authors can be the result of a regional metamorphism event that developed during the Laramide orogeny in northwestern Sonora.