Silurian to Cretaceous geological evolution of southern Mexico and its connection to the assembly and break-up of Western Equatorial Pangaea: geochronological constraints from the northern Sierra de Juárez Complex

Abstract

Abstract The Sierra de Juárez Complex (SJC) of southern Mexico contains an extensive geological record from Precambrian to Cenozoic, involving Rodinia, NW Gondwana, western equatorial Pangaea, and eastern peninsular Mexico. It is thus critical for palinspastic reconstructions and lithotectonic correlations, mainly between the Mexican and NW South America terranes. In this contribution, we investigate the tectonic evolution of the northern SJC from Silurian to the Lower Cretaceous on the basis of fieldwork, petrography, and zircon U–Pb geochronology by laser ablation–inductively coupled plasma mass spectrometry. Our results allow us to constrain five main geological events: (1) Middle Paleozoic sedimentation along NW Gondwana during transtensional tectonics; (2) volcanosedimentary activity between 292 and 281 Ma in NW Gondwana during Rheic Ocean closure; (3) early-middle Permian metamorphism related to flat-slab subduction postdating Pangaea assembly; (4) Lower–Middle Jurassic anatexis and magmatism coeval with regional shearing at c. 175 Ma influenced by transtensional tectonics along eastern peninsular Mexico during Pangaea tenure; and (5) intermediate to acid magmatism between c. 136 and 129 Ma, correlated with the Zongolica continental arc in southern Mexico, followed by deep-crustal shearing related to either the formation of the extensional Chivillas basin or the Upper Cretaceous–Cenozoic contractional episode documented in the Cuicateco Terrane.