Geodynamic Processes in the Trans-Mexican Volcanic Belt

The Trans-Mexican Volcanic Belt (TMVB) represents a complex zone of arc volcanism and crustal deformation that extends roughly 1,000 km across central Mexico. Its geodynamic framework is governed by the varied subduction geometries of the Cocos and Rivera oceanic plates beneath the North American plate, producing segmentation in volcanic activity, seismicity and crustal structure. In the western segment, a pronounced flat-slab regime of the Cocos plate reduces mantle wedge melting and suppresses volcanic output, whereas steep slab angles to the east promote a typical volcanic arc. Along the belt, slab tearing and lateral variations in slab dip modulate mantle flow pathways, creating heterogeneities in melt generation and surface volcanism. Crustal thickness and fault networks further influence magma storage and ascent, with geothermal reservoirs tapping heat where extensional basins and arc edifices coincide. These interlinked processes shape the timing, location and style of eruptions, control regional seismic hazards and underpin the TMVB’s significance as a natural laboratory for arc dynamics and as a resource for geothermal energy.

Research from Nature Portfolio

Recent studies have produced a high-resolution three-dimensional shear-wave velocity model of the Middle American subduction system, revealing pronounced along-strike variations in the Cocos plate beneath Mexico. This model illuminates high-velocity slab segments in the northern and southern TMVB that coincide with vigorous arc volcanism, while a central thick, high-velocity feature hinders mantle wedge development and suppresses magmatism. Evidence of slab tearing at the lateral edges of the Mexican flat slab emerged, demonstrating how such tears channel mantle flow and localise magma generation. These findings refine our understanding of how subduction geometry and slab integrity govern the uneven distribution of volcanoes along the belt.

Geodynamic Processes in the Trans-Mexican Volcanic Belt publication trend

The graph below shows the total number of articles in geodynamic processes in the trans-mexican volcanic belt across all publications each year (not limited to Nature Index journals).

Technical terms

Subduction: The process by which one tectonic plate descends beneath another into the mantle at a convergent boundary.

Flat slab: A subducting plate segment that travels horizontally beneath the overriding plate for a considerable distance before descending into the mantle.

Slab tearing: A break or gap that forms within a subducted plate, altering mantle flow and melt distribution.

Mantle wedge: The region of the upper mantle above a subducting slab and below the overriding plate, where flux melting often generates arc magmas.

Shear-wave velocity tomography: A seismic imaging technique that uses variations in shear-wave speeds to infer subsurface structure.

Moho discontinuity: The boundary separating the Earth’s crust from the underlying mantle, detectable by an abrupt change in seismic velocity.

References

1. Role of subduction dynamics on the unevenly distributed volcanism at the Middle American subduction system. Scientific Reports (2023).
2. Microearthquakes in the Guadalajara Metropolitan Zone, Mexico: evidence from buried active faults in Tesistán Valley, Zapopan. Natural Hazards (2023).
3. Flat-Slab Mechanics Transforming Double-Arc Expressions Along the Middle America Trench. Pure and Applied Geophysics (2024).
4. The Extended Continental Crust West of Islas Marías (Mexico). Frontiers in Earth Science (2021).