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.

h_e (m)

Required number in m. Station elevation above datum.

V_w (m/s)

Required number in m/s. Weathering-layer velocity.

V_r (m/s)

Required number in m/s. Replacement (datum) velocity.

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

Elevation static from station height above datum using the replacement-velocity method. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

t_stat (ms)

Returned number in ms. Static time shift to apply.

Polarity

Returned string. Advance or delay convention.

• 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.
• V_w must be at least 0.
• V_r 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.

• Coda Normalization Lapse Time Amplitude Correction

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• Near Fault Fling Step Velocity Pulse Calculator

  Fling-step peak velocity from static slip and rise time: v ≈ Δu / τ.