Seismic Hazard Analysis of Active Fault Systems

Seismic hazard analysis of active fault systems entails the quantitative assessment of the likelihood and potential impact of earthquake ruptures along faults that have exhibited motion in the late Quaternary. It integrates geological, geodetic and seismological observations to characterise fault geometry, slip rates and recurrence behaviours. Analyses range from probabilistic models of rupture timing to deterministic simulations of ground‐motion scenarios and surface displacement. Key elements include mapping fault traces, estimating long-term slip rates from geomorphic markers or palaeoseismic trenches, and modelling the stress interactions between adjacent fault segments. Modern approaches increasingly employ ensemble forecasting to account for uncertainties in earthquake recurrence and rupture propagation, as well as time-dependent models that incorporate viscoelastic relaxation and aftershock sequences. The global significance of this work lies in its direct application to seismic zoning, urban planning and infrastructure resilience, enabling policymakers and engineers to prioritise mitigation measures and refine building codes in tectonically active regions.

Research from Nature Portfolio

Recent studies have advanced probabilistic forecasting by integrating multiple statistical models of recurrence intervals derived from palaeoseismic trench records. By applying Bayesian model-averaging, time-dependent rupture probabilities are generated for numerous fault segments worldwide, improving the representation of measurement errors and model selection uncertainty. These ensemble forecasts yield spatially explicit rupture likelihoods over multi-decadal timescales, highlighting the absence of a universal recurrence law and the need for tailored model combinations when data are sparse.

Complementary research has exploited space-based geodetic measurements—such as high-resolution Interferometric Synthetic Aperture Radar and continuous GNSS—to map co-seismic and inter-seismic deformation with unprecedented detail. These observations support dynamic models of fault network evolution, revealing how changes in crustal stress following large events can modulate strain accumulation on neighbouring faults. The synthesis of surface rupture mapping and subsurface slip inversion now informs time-dependent hazard scenarios that capture both rapid rupture cascades and long-term landscape evolution.

Seismic Hazard Analysis of Active Fault Systems publication trend

The graph below shows the total number of articles in seismic hazard analysis of active fault systems across all publications each year (not limited to Nature Index journals).

Technical terms

Active fault system: A network of faults that have experienced movement during the late Quaternary and are capable of future seismic rupture.

Seismic hazard analysis: The quantitative evaluation of earthquake occurrence probabilities and associated ground-motion or surface-rupture effects over specified timeframes.

Palaeoseismic record: Geological evidence, such as sedimentary layers and fault-scarps, used to date and characterise past earthquake events.

Bayesian model-averaging: A statistical approach combining multiple predictive models weighted by their posterior probabilities to account for model uncertainty.

Satellite-geodetic measurement: The use of orbital sensors (e.g., GNSS, InSAR) to monitor crustal deformation and fault slip at high spatial and temporal resolution.

Coseismic slip: The displacement that occurs on a fault plane during the rupture process of an earthquake.

Recurrence interval: The average time between successive ruptures on a given fault segment, inferred from geological or historical records.

References

1. Earthquake forecasting from paleoseismic records. Nature Communications (2024).
2. The role of space-based observation in understanding and responding to active tectonics and earthquakes. Nature Communications (2016).
3. Fault Orientation Trumps Fault Maturity in Controlling Coseismic Rupture Characteristics of the 2021 Maduo Earthquake. AGU Advances (2024).
4. One tune, many tempos: Faults trade off slip in time and space to accommodate relative plate motions. Earth and Planetary Science Letters (2024).