Tectonic Evolution and Geochemistry of Madagascar

Madagascar’s tectonic history is rooted in the Neoproterozoic assembly of eastern Gondwana, marked by the progressive closure of the Mozambique Ocean and successive phases of orogenesis. Ancient Archean and Proterozoic terranes form the continental core, overprinted by Neoproterozoic to Palaeozoic fold belts and Phanerozoic rift systems. Subduction, continental collisions and intraplate volcanism have sculpted a complex lithospheric architecture, while multiple uplift and erosion pulses since the Late Cretaceous have shaped the present-day topography. Geochemical investigations across metamorphic suites, alkaline volcanic fields and flood basalt provinces reveal diverse mantle sources—from enriched lithospheric peridotites to plume-related domains—and significant crustal assimilation. Isotopic and trace-element data elucidate the timing of crust-mantle interactions, the role of edge-driven convection in driving asthenospheric flow, and the influence of mantle-derived fluids in mineralisation. This integrated framework enhances understanding of crustal growth, resource potential and landscape evolution in a globally significant continental fragment.

Research from Nature Portfolio

Recent studies have refined the timing and mechanics of Neoproterozoic subduction along the eastern Gondwana margin. New reconstructions propose two distinct phases of ocean-floor consumption—first under a north–south subduction geometry (870–750 Ma) and later via an east–west system (720–650 Ma). By integrating geological, palaeomagnetic and true polar wander constraints, these models capture the closure of the Mozambique Ocean and demonstrate a fundamental reorganisation of convergent margins that underpinned the final assembly of Gondwana and influenced subsequent crustal architecture.

Tectonic Evolution and Geochemistry of Madagascar publication trend

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

Technical terms

Subduction system: A convergent plate boundary where one lithospheric plate descends beneath another into the mantle.

Orogenic belt: A region of mountain building formed by crustal deformation and metamorphism during continental collision or subduction.

Asthenosphere: The ductile layer of the upper mantle beneath the rigid lithosphere that can flow and host convective currents.

Metasomatism: The process by which rocks are chemically altered through interaction with percolating fluids, introducing or removing elements.

Trace-element signature: The pattern and concentration of minor and trace elements in a rock or mineral that reflect its source characteristics and evolutionary history.

References

1. Neoproterozoic reorganization of the Circum- Mozambique orogens and growth of megacontinent Gondwana. Communications Earth & Environment (2023).
2. Numerical Modeling of Mantle Flow Beneath Madagascar to Constrain Upper Mantle Rheology Beneath Continental Regions. Journal of Geophysical Research: Solid Earth (2020).
3. Alkaline rocks of the Bobaomby volcanic field point to a petrogenetic link between Comoros and northern Madagascar lithosphere. International Journal of Earth Sciences (2022).
4. Linking uplift, erosion, and sedimentation using landscape evolution models: Madagascar since the Late Cretaceous. Earth Surface Processes and Landforms (2022).
5. A New Insight into the Genesis of Graphite Deposits in Madagascar Using U–Pb Zircon Dating and Electron Microprobe Analysis. Minerals (2024).
6. Feeding system and mantle sources of the southern and western sector of the Madagascar flood basalt province, and comparisons with Southwest Indian Ridge “anomalous” basalts. Lithos (2023).