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.

SNR (dB)

Required number in dB. Signal-to-noise ratio of the pick.

thr (dB)

Optional number in dB. Acceptance threshold.

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

Screen first-break picks against a minimum signal-to-noise ratio in decibels. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Valid?

Returned boolean. Whether the pick passes the screen.

margin (dB)

Returned number in dB. SNR margin over the threshold.

• 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.
• 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.

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