Tectonic Evolution and Geochronology of Southern Mexico

Southern Mexico occupies a complex junction between the Cocos, Farallon/Cocos and North American plates, where subduction, slab tears and oblique convergence have moulded the present‐day architecture over the past 100 million years. Early Mesozoic extension was followed by Cretaceous arc magmatism that built the Sierra Madre del Sur, while terrane accretion and forearc shortening in the Late Cretaceous–Paleogene gave rise to thickened crust and high‐grade metamorphism in the Oaxacan Complex. Subsequent Miocene‐Pliocene slab‐tear migration and shifts in subduction angle drove episodic pulses of granodioritic to dacitic magmatism, migrating the locus of volcanism inland and linking the Sierra Madre del Sur with the Trans-Mexican Volcanic Belt. Contemporaneously, forearc blocks such as the Xolapa sliver were sheared off the overriding plate by trench-parallel strike-slip zones, accommodating oblique convergence and redistributing strain. U–Pb zircon geochronology, paired with thermobarometry and isotopic tracing, has refined the timing of magmatic pulses, metamorphic peaks and fault activity, revealing multi-episodic crustal growth, recycling and lateral displacement. This interplay of processes underlies frequent seismicity, metallogenic enrichment and the transition from Cordilleran orogen to continental margin.

Research from Nature Portfolio

No recent Nature Portfolio content available.

Tectonic Evolution and Geochronology of Southern Mexico publication trend

The graph below shows the total number of articles in tectonic evolution and geochronology of southern mexico across all publications each year (not limited to Nature Index journals).

Technical terms

Oblique subduction: Convergence in which the incoming plate descends at an angle to the trench, partitioning motion into trench-normal and trench-parallel components.

Forearc sliver: A narrow block of overriding crust between the trench-parallel strike-slip fault and the volcanic arc that moves independently of the main plate mass.

U–Pb geochronology: Radiometric dating method using the decay of uranium to lead in minerals such as zircon and baddeleyite to establish crystallisation and metamorphic ages.

Granulite-facies metamorphism: High-temperature, moderate-pressure metamorphic conditions producing minerals such as garnet and orthopyroxene in lower continental crust.

Slab tear: A break or gap in a subducting oceanic plate that can localise magmatism and alter the thermal and flow regimes of the mantle wedge.

References

1. Active 650-km Long Fault System and Xolapa Sliver in Southern Mexico. Frontiers in Earth Science (2020).
2. Activity of crustal faults and the Xolapa sliver motion in Guerrero–Oaxaca forearc of Mexico, from seismic data. Earth, Planets and Space (2019).
3. High-Temperature Metamorphic Garnets from Grenvillian Granulites of Southwestern Oaxacan Complex (Southern Mexico): Petrology, Geochemistry, Geothermobarometry, and Tectonic Implications. Minerals (2021).
4. Multi‐episodic formation of baddeleyite and zircon in polymetamorphic anorthosite and rutile‐bearing ilmenitite from the Chiapas Massif Complex, Mexico. Journal of Metamorphic Geology (2022).
5. Petrogenetic evolution of the Jalapa del Marqués pluton: Miocene arc magmatism in southern Mexico and its tectonic implications. Lithos (2024).
6. Metallogeny of the state of Oaxaca, Mexico. Journal of Maps (2022).