Corner Frequency Stress Drop Consistency Checker
Invert the Brune relation fc = 0.49·β·(Δσ/M₀)^(1/3) for stress drop Δσ = M₀·(fc/(0.49·β))³ given the moment and compare with a claimed Δσ; no rigidity term is needed because Δσ/M₀ replaces it.
Description
Invert the Brune relation fc = 0.49·β·(Δσ/M₀)^(1/3) for stress drop Δσ = M₀·(fc/(0.49·β))³ given the moment and compare with a claimed Δσ; no rigidity term is needed because Δσ/M₀ replaces it.
Corner Frequency Stress Drop Consistency Checker is a focused tool for the following task. Invert the Brune relation fc = 0.49·β·(Δσ/M₀)^(1/3) for stress drop Δσ = M₀·(fc/(0.49·β))³ given the moment and compare with a claimed Δσ; no rigidity term is needed because Δσ/M₀ replaces it. It reports Δσ_inv, Consistent? from the values you provide rather than inventing measurements, coefficients, or professional judgment that are not part of the input.
When to use Corner Frequency Stress Drop Consistency Checker
Use this seismology calculation to reproduce a stated convention, screen observations, or compare scenarios whose units, coordinate conventions, catalog selection, and model assumptions are known.
- f_c (Hz)
- Required number in Hz. Observed corner frequency.
- M₀ (N·m)
- Required number in N·m. Seismic moment.
- Δσ_claim (bar)
- Required number in bar. Claimed stress drop.
- β (km/s)
- Optional number in km/s. Shear velocity.
The cited overview of Seismology supplies background for the terminology and domain context used by this tool.1
How Corner Frequency Stress Drop Consistency Checker works
Invert the Brune relation fc = 0.49·β·(Δσ/M₀)^(1/3) for stress drop Δσ = M₀·(fc/(0.49·β))³ given the moment and compare with a claimed Δσ; no rigidity term is needed because Δσ/M₀ replaces it. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.
- Δσ_inv (bar)
- Returned number in bar. Stress drop implied by fc and M₀.
- Consistent?
- Returned boolean. Whether inverted value is within a factor of two.
Limitations and assumptions
- Earth structure, source geometry, path effects, site response, instrument response, catalog completeness, uncertainty, and the fitted range can dominate the accuracy of simplified seismic calculations.
- f_c must be at least 0.
- M₀ must be at least 0.
- Δσ_claim must be at least 0.
- Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.
Alternative or Complementary approaches
For analysis or hazard decisions, retain uncertainty and provenance and compare the result with waveform processing, calibrated regional models, and guidance from qualified seismologists or the responsible agency.
References
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Seismology — Wikipedia contributors
Similar or alternative tools
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- Brune Source Time Duration From Corner Calculator
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