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Updated: Jun 19, 2026
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Data Processing Methods for 3D Seismic Imaging of Subsurface Volcanoes: Applications to the Tarim Flood Basalt
Published on: August 7, 2017
Multiplicative cascades and seismicity in natural time
N V Sarlis1, E S Skordas, P A Varotsos
1Department of Physics, Solid State Section and Solid Earth Physics Institute, University of Athens, Panepistimiopolis, Zografos, 157 84 Athens, Greece.
Summary
This study introduces natural time analysis to understand earthquake self-similarity origins. It links variance in natural time to the Gutenberg-Richter law parameter and finds stronger magnitude correlations for closer seismic events.
Area of Science:
- Geophysics
- Statistical Physics
- Seismology
Background:
- Self-similarity in natural phenomena is often analyzed using statistical methods.
- Understanding the origins of self-similarity in earthquake data is crucial for seismic analysis.
- Previous studies have explored various statistical properties of earthquake occurrences.
Purpose of the Study:
- To distinguish between different origins of self-similarity in earthquake data using natural time analysis.
- To investigate the relationship between the variance in natural time and the Gutenberg-Richter law parameter.
- To analyze temporal and magnitude correlations in earthquake data.
Main Methods:
- Application of natural time analysis to earthquake data.
- Employing multiplicative cascades within the natural time framework.
- Explicitly relating the variance kappa(1) (chi(2)-chi(2)) to the Gutenberg-Richter law parameter 'b'.
- Studying temporal and magnitude correlations in original earthquake records.
Main Results:
- Natural time analysis successfully distinguishes between process memory and infinite variance as origins of self-similarity.
- The most probable value of variance kappa(1) is explicitly linked to the Gutenberg-Richter parameter 'b' for shuffled earthquake data.
- Magnitude correlations are found to be stronger for earthquakes occurring closer in time, with a maximum interoccurrence time range observed.
Conclusions:
- Natural time analysis provides a novel approach to understanding earthquake self-similarity.
- The study establishes a quantitative link between natural time variance and a key parameter of the Gutenberg-Richter law.
- The findings highlight the presence and strengthening of temporal and magnitude correlations in earthquake sequences.
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