Tectonic Evolution and Crustal Dynamics of Continental Margins

Continental margins record the transition from rigid continental lithosphere to oceanic plates and host a spectrum of tectonic processes that govern basin formation, crustal thinning and magmatic activity. Rift initiation is usually marked by lithospheric stretching and fault block rotation, resulting in hyperextended continental crust and exhumation of mantle peridotites. Continued extension leads to the rift-to-drift transition, when steady-state seafloor spreading begins and true oceanic crust is established. Passive margins may remain amagmatic or undergo focused magmatism that influences crustal architecture and thermal structure. Active margins, conversely, involve subduction, accretionary prism development and associated volcanism that modify margin shape and dynamics. Throughout these stages, interactions between plume activity, slab rollback and mantle flow drive variations in sedimentation, structural segmentation and seismic hazard. Understanding the interplay of these processes is vital for hydrocarbon prospectivity, geothermal potential and assessing earthquake and tsunami risk along continental edges.

Research from Nature Portfolio

Recent studies have employed high-resolution seismic imaging coupled with geodynamic modelling to quantify the role of water in the upper mantle beneath marginal basins. New seismic velocity models show that subduction-derived fluids can be retained in the mantle for tens of millions of years after slab detachment, reducing shear velocities by several per cent and altering the rheology of the lithosphere–asthenosphere boundary. Thermal-dynamic simulations further indicate that water content of a few hundred parts per million, combined with lower continental crustal material, accounts for anomalies in mantle density and heat flow. These findings refine our understanding of how volatile cycling influences margin evolution, controls magma production during break-up and affects post-rift subsidence patterns.

Tectonic Evolution and Crustal Dynamics of Continental Margins publication trend

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

Technical terms

Continental margin: The outer edge of continental crust transitioning into oceanic lithosphere, comprising shelf, slope and rise regions.

Crustal hyperextension: Extreme thinning of continental crust due to prolonged lithospheric stretching, often exposing mantle rocks.

Passive margin: A non-tectonically active continental margin formed by rifting and subsequent seafloor spreading without nearby plate boundary forces.

Rift-to-drift transition: The stage when a rifted continental margin evolves into an oceanic spreading centre and true oceanic crust forms.

Subduction zone: A convergent plate boundary where one lithospheric plate sinks beneath another into the mantle, driving magmatism and orogenesis.

Seismic tomography: A method for imaging subsurface structures by inverting seismic wave velocity data to infer variations in temperature, composition and fluid content.

References

1. Mantle heterogeneity caused by trapped water in the Southwest Basin of the South China Sea. Nature Communications (2023).
2. Multilayer Densities of the Crust and Upper Mantle in the South China Sea Using Gravity Multiscale Analysis. Remote Sensing (2023).
3. Lateral evolution of the rift-to-drift transition in the South China Sea: Evidence from multi-channel seismic data and IODP Expeditions 367&368 drilling results. Earth and Planetary Science Letters (2020).