First Motion Polarity Beachball Quadrant Picker
Summarize P-wave first-motion polarity statistics into beachball quadrant occupancy.
Description
Summarize P-wave first-motion polarity statistics into beachball quadrant occupancy.
First Motion Polarity Beachball Quadrant Picker is a focused tool for the following task. Summarize P-wave first-motion polarity statistics into beachball quadrant occupancy. It reports +%, Call %, Quality from the values you provide rather than inventing measurements, coefficients, or professional judgment that are not part of the input.
When to use First Motion Polarity Beachball Quadrant Picker
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.
- n_up
- Required integer. Number of up (compression) readings.
- n_down
- Required integer. Number of down (dilatation) readings.
- n_nodal
- Required integer. Readings too near nodal planes to call.
The cited overview of Seismic wave supplies background for the terminology and domain context used by this tool.1
How First Motion Polarity Beachball Quadrant Picker works
Summarize P-wave first-motion polarity statistics into beachball quadrant occupancy. Inputs are interpreted exactly in the displayed units and the calculation returns the following fields without presentation rounding.
- +% (%)
- Returned number in %. Share of compressional readings among called polarities.
- Call % (%)
- Returned number in %. Fraction of readings usable for mechanism.
- Quality
- Returned string. Quadrant sampling quality.
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.
- n_up must be at least 0.
- n_down must be at least 0.
- n_nodal 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
-
Seismic wave — Wikipedia contributors
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