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.

Es (J)

Required number in J. Radiated seismic energy.

M₀ (N·m)

Required number in N·m. Seismic moment.

Δσ (Pa)

Optional number in Pa. Stress drop.

μ (Pa)

Optional number in Pa. Rigidity.

The cited overview of Seismology supplies background for the terminology and domain context used by this tool.^[1]

Seismic efficiency η = Es / E_total with E_total = (Δσ/2μ)·M₀. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

η% (%)

Returned number in %. Fraction of released energy radiated.

E_tot (J)

Returned number in J. Estimated total released energy.

• 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.
• Es must be at least 0.
• M₀ must be at least 0.
• Use finite inputs in the displayed units, preserve source measurements and assumptions, and independently verify consequential decisions.

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.

• Radiated Energy Moment Ratio Calculator

  Dimensionless ratio of radiated seismic energy to seismic moment.

• AGC Gain Step Artifact Flagger

  Flag windows where automatic-gain-control steps coincide with event energy.

• Apparent Stress Energy Ratio Calculator

  Apparent stress σ_app = μ · Es / M₀ in megapascals.