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Published on: June 28, 2015
Entropy production and self-organized (sub)criticality in earthquake dynamics
1University of Edinburgh, School of GeoSciences, Grant Institute, West Mains Road, Edinburgh EH9 3JW, UK. ian.main@ed.ac.uk
Summary
Maximum entropy production (MEP) drives self-organized criticality in earthquake populations. This thermodynamic principle explains observed earthquake behaviors like power-law scaling and low seismic efficiency, suggesting a near-critical state.
Area of Science:
- Geophysics
- Statistical Mechanics
- Complex Systems
Background:
- Earthquake dynamics often exhibit self-organized criticality (SOC).
- Understanding the thermodynamic drivers of SOC in natural systems remains a challenge.
- Previous models often described systems near, but not strictly at, criticality.
Purpose of the Study:
- To derive an analytical expression for entropy production in earthquake populations.
- To test the hypothesis that maximum entropy production (MEP) drives SOC in earthquake models.
- To link MEP to observable earthquake characteristics.
Main Methods:
- Derived an analytical expression for entropy production based on Dewar's formulation.
- Applied the formulation to the Olami-Feder-Christensen numerical model.
- Assumed power-law rheology relating driving stress and strain rate.
Main Results:
- MEP occurs near the critical state in the earthquake model.
- MEP is associated with low seismic efficiency and broad-bandwidth power-law scaling.
- These results align with observed phenomena in natural earthquake populations.
Conclusions:
- MEP provides a thermodynamic basis for SOC in earthquake dynamics.
- The MEP state exhibits characteristics consistent with natural earthquakes.
- Predictability in earthquake systems is limited by proximity to criticality and data resolution.
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