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Updated: May 21, 2025
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Large-scale Reconstructions and Independent, Unbiased Clustering Based on Morphological Metrics to Classify Neurons in Selective Populations
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Leveraging spurious Omori-Utsu relation in the nearest-neighbor declustering method
Andreu Puy1, Jordi Baró2,3, Jörn Davidsen4,5
1Universitat Politècnica de Catalunya, Departament de Física, Campus Nord B4, 08034 Barcelona, Spain.
Physical Review. E
|March 19, 2025
Summary
Identifying earthquake aftershocks is crucial for seismic hazard assessment. This study reveals that standard methods can produce misleading results, but a robust technique helps confirm the presence of aftershocks, even in complex natural earthquake swarms.
Area of Science:
- Earthquake science
- Seismology
- Geophysics
Background:
- Earthquake-induced stress changes commonly trigger aftershocks.
- Aftershock identification is vital for seismic hazard assessment.
- Challenges arise from fluid migration and injections causing variable earthquake patterns.
Purpose of the Study:
- To analyze the impact of declustering methods on earthquake catalog analysis.
- To develop a robust method for identifying aftershocks in complex seismic catalogs.
- To investigate earthquake triggering and productivity relations.
Main Methods:
- Analytical modeling of earthquake triggering.
- Numerical simulations of seismic activity.
- Application of a nearest-neighbor declustering method.
- Analysis of Omori-Utsu and productivity relations.
Main Results:
- Earthquake catalogs lacking triggering information can yield spurious Omori-Utsu and productivity relations.
- The Omori-Utsu exponent's robustness to new parameters aids in aftershock detection.
- A natural swarm catalog was found to be dominated by aftershocks.
Conclusions:
- Standard declustering methods may require refinement for accurate seismic hazard assessment.
- A robust method can reliably identify aftershocks, even in complex scenarios.
- Natural earthquake swarms can be largely composed of triggered events.
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