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Updated: Jul 12, 2026

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Kinematic History of a Salient-recess Junction Explored through a Combined Approach of Field Data and Analog Sandbox Modeling
Published on: August 5, 2016
Seismic evidence for an earthquake nucleation phase
Summary
Earthquakes begin with a slow seismic nucleation phase, observed across various magnitudes. This initial phase
Area of Science:
- Seismology
- Earthquake physics
- Geophysics
Background:
- Earthquakes initiate with a seismic nucleation phase.
- This phase is characterized by a low moment release rate.
Purpose of the Study:
- To analyze the characteristics of the seismic nucleation phase.
- To determine the relationship between the nucleation phase and the final earthquake size.
Main Methods:
- Analysis of near-source seismic observations.
- Examination of 30 earthquakes ranging in moment magnitude from 2.6 to 8.1.
Main Results:
- The nucleation phase was observed in all studied earthquakes.
- Nucleation phase duration and size scale with the eventual earthquake magnitude.
- Moment release during nucleation was irregular and localized.
- Moment rate exhibited quadratic growth as rupture propagated.
Conclusions:
- The nucleation process significantly influences the final size of an earthquake.
- Understanding nucleation is key to predicting earthquake behavior.
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