Tectonic Evolution of Southeast Asia

Southeast Asia occupies a complex junction of the Eurasian, Indian–Australian, Pacific and Philippine Sea plates, forming one of the world’s most intricate accretionary orogens. Beginning in the Paleozoic–Mesozoic, fragments derived from Gondwana and intra-oceanic arcs rifted, drifted and collided with the growing Eurasian margin, assembling microcontinental blocks and oceanic basins. Jurassic rifting detached lithospheric fragments from northern Australia, which later accreted as discrete terranes above the Sundaland subduction zone. Continued Cretaceous subduction of the Paleo-Pacific plate generated widespread magmatism and crustal thickening, followed by Eocene–Oligocene opening of the South China Sea back-arc basin. Neogene convergence reactivated major strike-slip systems, notably the Sumatra fault and the Philippine Fault, while foreland basins formed in Myanmar and western Borneo. This evolving mosaic controls seismic and tsunami hazards, underpins major mineral-metallogenic belts, and defines hydrocarbon-rich basins in the South China and Andaman seas. As a natural laboratory for accretionary processes and microcontinent assembly, Southeast Asia offers critical insights into orogenic cycle dynamics, resource distribution and geohazard mitigation on a global scale.

Research from Nature Portfolio

Recent studies have exploited high-resolution optical and SAR satellite data to refine the kinematics of the Palu–Koro fault system in Central Sulawesi. Detailed interferometric mapping reveals that the 2018 Mw 7.5 earthquake ruptured multiple onshore and offshore segments, with up to 6 m left-lateral slip and evidence for supershear propagation. By constraining three-dimensional ground displacements and fault geometry, this work updates fault-segmentation models and improves assessments of submarine landslide and tsunami potential in complex strike-slip networks.

Tectonic Evolution of Southeast Asia publication trend

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

Technical terms

Accretionary orogen: A mountain belt formed by the progressive addition of oceanic and continental fragments to a continental margin.

Subduction: The process whereby one tectonic plate sinks beneath another into the mantle along a convergent boundary.

Microcontinental fragment: A small block of continental crust that has rifted from a larger landmass and may later accrete to another plate.

Suture zone: A linear boundary marking the collision and welding of distinct tectonic blocks or terranes.

Strike-slip fault: A fault on which the predominant displacement is horizontal and parallel to the fault strike.

Supershear rupture: An earthquake rupture that propagates along a fault faster than the shear-wave speed of the surrounding rock.

References

1. Sentinel optical and SAR data highlights multi-segment faulting during the 2018 Palu-Sulawesi earthquake (Mw 7.5). Scientific Reports (2020).
2. The 2018 Mw 7.5 Palu Earthquake: A Supershear Rupture Event Constrained by InSAR and Broadband Regional Seismograms. Remote Sensing (2019).
3. Finding Argoland: Reconstructing a microcontinental archipelago from the SE Asian accretionary orogen. Gondwana Research (2024).
4. Mesozoic Paleo-Pacific Subduction Beneath SW Borneo: U-Pb Geochronology of the Schwaner Granitoids and the Pinoh Metamorphic Group. Frontiers in Earth Science (2020).
5. Geochemistry and zircon UPb geochronology of Late Mesozoic igneous rocks from SW Vietnam – SE Cambodia: Implications for episodic magmatism in the context of the Paleo-Pacific subduction. Lithos (2021).