Magmatic Processes and Geological Evolution in Patagonia and Antarctica

The geological history of Patagonia and Antarctica is characterised by prolonged episodes of magmatism driven by the dynamics of the Gondwana margin. From early Palaeozoic arc systems to Late Triassic–Jurassic batholith emplacement and Cenozoic adjustments, magmatic activity has been governed by subduction geometry, slab dynamics and occasional mantle plume interactions. Intrusive suites record shifts from juvenile asthenospheric melts to crustally influenced magmas, while extrusive successions reflect changing convergence rates and slab angles. Terrane assembly, accretionary complexes and continental‐arc migration have shaped the crustal architecture, with major pulses during the Ordovician, Permian and Triassic accompanying orogenic events. These processes underpin the formation of large igneous provinces, mineralised districts and hydrocarbon‐bearing basins. Integrated geochronology, geochemistry and geophysical reconstructions now yield refined models of slab break-off, arc migration and plume-subduction interplay, highlighting their global relevance for crustal growth and resource distribution.

Research from Nature Portfolio

Recent studies have revealed a temporal evolution in radiogenic isotopes of Antarctic Peninsula arc magmas that departs from spatial juvenile-to-evolved trends typical of continental arcs. Over the Cenozoic these magmas have become increasingly juvenile, attributed to the slow subduction of young lithosphere and a reduction in convergence rate that narrowed the arc and limited crustal assimilation. In parallel, integrated plate-kinematic and mantle‐seismic analyses have identified a mid-Permian slab break-off event beneath southwestern Pangea that gave rise to a vast silicic magmatic province; this represents one of the oldest geophysically constrained break-off signatures and reframes our understanding of large igneous province formation. Foundational work on plume-subduction interaction beneath Patagonia has demonstrated that early Jurassic plume-derived melts refertilised the subcontinental mantle, creating a gold-rich source that, when flushed by subduction fluids, generated major auriferous provinces.

Magmatic Processes and Geological Evolution in Patagonia and Antarctica publication trend

The graph below shows the total number of articles in magmatic processes and geological evolution in patagonia and antarctica across all publications each year (not limited to Nature Index journals).

Technical terms

Subduction: Descent of oceanic lithosphere beneath an adjacent plate at a convergent margin.

Slab break-off: Detachment of a subducting tectonic plate segment from its trailing lithosphere.

Continental arc: Magmatic belt formed above a subduction zone adjacent to continental crust.

Detrital zircon geochronology: Age dating of sedimentary zircons to trace source terranes and tectonic events.

Radiogenic isotopes: Isotope ratios altered by radioactive decay, used to infer magma sources and crustal evolution.

Refertilisation: Enrichment of the lithospheric mantle by external melts or fluids, enhancing its fertility for magma generation.

References

1. Palaeozoic – Early Mesozoic geological history of the Antarctic Peninsula and correlations with Patagonia: Kinematic reconstructions of the proto-Pacific margin of Gondwana. Earth-Science Reviews (2023).
2. A temporal control on the isotopic compositions of the Antarctic Peninsula arc. Communications Earth & Environment (2024).
3. Catastrophic slab loss in southwestern Pangea preserved in the mantle and igneous record. Nature Communications (2022).
4. Plume-subduction interaction forms large auriferous provinces. Nature Communications (2017).
5. A revised interpretation of the Chon Aike magmatic province: Active margin origin and implications for the opening of the Weddell Sea. Lithos (2021).
6. Autochthonous v. accreted terrane development of continental margins: a revised in situ tectonic history of the Antarctic Peninsula. Journal of the Geological Society (2015).