Seismology and Tectonics of Continental Interiors

Seismology and tectonics of continental interiors examine the processes and structures that govern earthquake occurrence, deformation and lithospheric evolution away from plate boundaries. Intraplate seismicity arises on pre-existing faults reactivated by far-field plate forces, gravitational body forces or mantle flow. Heterogeneous lithospheric architecture, including variations in thickness, composition and thermal state, exerts primary control on stress concentration and seismic hazard in stable continental regions. State-of-the-art seismic tomography, receiver-function analysis and geodynamic modelling now resolve thermal and compositional variations in the upper mantle and crust at resolutions of tens of kilometres, revealing how variations in mantle asthenospheric flow, lithosphere–asthenosphere boundary topography and crustal stress fields localise intraplate deformation. Meanwhile, advances in deep-learning earthquake detection and moment-tensor inversion are uncovering complex rupture geometries in exceptionally shallow events, reshaping our understanding of seismogenesis in the uppermost crust. Integrating geodetic observations with dynamic three-dimensional models allows quantitative assessment of crustal strain rates and stresses in continental interiors, offering new insights into seismic risk management, resource exploration and the long-term stability of continental lithosphere.

Research from Nature Portfolio

Recent studies have used fully dynamic three-dimensional modelling with data assimilation to demonstrate that lithospheric thickness contrasts and asthenospheric flow interactions control intraplate deformation patterns in tectonically active continental interiors. These models reveal that step changes in lithospheric thickness, for example at the boundary of extended basins, focus stress and drive seismicity in regions far from plate margins. In parallel, deep-learning enhanced seismic catalogues combined with differential-travel-time relocation have uncovered complex fault networks and non-double-couple moment-tensor components in extremely shallow intraplate earthquakes. Detailed analysis of a magnitude 5.1 event in the eastern United States showed surface rupture on blind strike-slip and reverse faults, challenging conventional views of stable continental crust behaviour and highlighting the need to reassess seismic hazard in such regions.

Seismology and Tectonics of Continental Interiors publication trend

The graph below shows the total number of articles in seismology and tectonics of continental interiors across all publications each year (not limited to Nature Index journals).

Technical terms

Lithosphere: The rigid outer layer of the Earth comprising crust and uppermost mantle.

Asthenosphere: The partially molten, mechanically weak zone beneath the lithosphere that facilitates plate motion.

Intraplate earthquake: Seismic event occurring within a tectonic plate rather than at its boundary.

Seismic tomography: Imaging technique that uses seismic waves to infer three-dimensional velocity structure of the crust and mantle.

Moment tensor inversion: Mathematical method to determine the orientation and nature of fault slip from seismic waveforms.

References

1. Western US intraplate deformation controlled by the complex lithospheric structure. Nature Communications (2024).
2. Complex rupture dynamics of the extremely shallow August 2020 M5.1 Sparta, North Carolina earthquake. Communications Earth & Environment (2024).
3. Mantle thermochemical variations beneath the continental United States through petrologic interpretation of seismic tomography. Earth and Planetary Science Letters (2023).
4. Preliminary Observations of the 5 April 2024 Mw 4.8 New Jersey Earthquake. The Seismic Record (2024).
5. Gravitational body forces focus North American intraplate earthquakes. Nature Communications (2017).
6. Aeromagnetic Data Reveal Potential Seismogenic Basement Faults in the Induced Seismicity Setting of Oklahoma. Geophysical Research Letters (2018).