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.

φ (°)

Required number in °. Fault strike.

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

Nodal and maximum-radiation azimuths of the strike-slip S-wave pattern R ∝ sin 2(az − φ). Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.

Nodes (°)

Returned list in °. Azimuths of zero radiation.

Maxima (°)

Returned list in °. Azimuths of peak radiation.

• 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.
• φ 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.

• Synthetic Strike-Slip Polarity Data Generator

  Generate synthetic P-wave polarity training data for a strike-slip-dominant focal mechanism.

• Apparent Dip Along Section Line Calculator

  Apparent dip on a section making angle α with the strike: tan(δ_app) = tan(δ)·|sin α|.

• Characteristic Earthquake Magnitude Window Lookup

  Estimate characteristic magnitude from a fault length using the Wells & Coppersmith strike-slip relation.