Reduced Displacement Tremor Radius Calculator
Surface-wave reduced displacement DR=A√(rλ) with all lengthsCM and outputCM², instrument response/distance correction independently matched, not tremor energy or eruption forecast. Caller independently establishes units, regime, calibration and applicability; this does not establish design-code compliance, authenticity, operational safety, treatment efficacy or a validated forecast.
Description
Reduced displacement normalizes an observed surface-wave displacement with source distance and wavelength.
Reduced displacement normalizes an observed surface-wave displacement with source distance and wavelength.1
This implementation uses centimetres throughout, giving a reduced displacement in square centimetres.
When to use Reduced Displacement Tremor Radius Calculator
Use this tool when you need to reproduce the stated calculation from measured records or independently selected model inputs. Prepare matched observations and independently established site, specimen, units, datum, and calibration context.
How to use Reduced Displacement Tremor Radius Calculator and understand its results
- Prepare matched observations and independently established site, specimen, units, datum, and calibration context.
- Enter observedTremorDisplacementCm, callerMatchedSourceDistancesCm, callerMatchedSurfaceWaveLengthsCm, following the field table and rules below, then run the tool.
- Read surfaceWaveReducedDisplacementsCm2. Use the output meanings below to interpret units, signs, flags, and any nested result fields.
- Correct reported input issues and run again. For a successful result, check the stated evidence coverage and assumptions before using it in your review.
| Input field | Meaning | Value type | Requirement |
|---|---|---|---|
| observedTremorDisplacementCm | Observed tremor displacement cm | list of number | Required |
| callerMatchedSourceDistancesCm | Caller matched source distances cm | list of number | Required |
| callerMatchedSurfaceWaveLengthsCm | Caller matched surface wave lengths cm | list of number | Required |
Use aligned nonempty displacement, distance, and wavelength lists in centimetres. Displacements must be nonnegative; distances and wavelengths must be positive. Instrument response and the surface-wave interpretation must already be matched independently.
DR_i = amplitude_i × √(distance_i × wavelength_i) Symbols follow the input and output meanings and the calculation rules above.
| Output field | Meaning | Value type |
|---|---|---|
| surfaceWaveReducedDisplacementsCm2 | Surface wave reduced displacements cm2 | list of number |
{
"input": {
"observedTremorDisplacementCm": [
1,
2
],
"callerMatchedSourceDistancesCm": [
100,
400
],
"callerMatchedSurfaceWaveLengthsCm": [
100,
100
]
},
"output": {
"surfaceWaveReducedDisplacementsCm2": [
100,
400
]
}
}Limitations and assumptions
Interpretation requires independently matched observations, units, site or specimen, and calibration. The calculation does not establish geological identity, operating safety, or an eruption forecast.
Missing required fields, unknown fields, wrong types, and violated calculation rules are input issues. Numeric values must be finite; nonfinite results are rejected. Evidence arrays must be dense, with no missing cells. Numeric observation lists allow at most 10,000 entries, subject to any smaller bounds stated above.
Alternative or Complementary methods
For a related review, use Volcanic Lightning Flash Count Proxy Tool: Volcanic lightning observations depend on how long a detector watched and what fraction of flashes it could detect. Correcting matched counts for detection coverage produces an observed flash rate, rather than an ash production estimate. For a complementary step, use Dormancy Reactivation Risk Score Calculator: An unrest score is a weighted summary of evidence under a chosen scoring policy. Missing evidence has its own weight, so the known-evidence score and coverage should be read together.
References
Similar or alternative tools
- Volcanic Lightning Flash Count Proxy Tool
Volcanic lightning observations depend on how long a detector watched and what fraction of flashes it could detect. Correcting matched counts for detection coverage produces an observed flash rate, rather than an ash production estimate.
- Dormancy Reactivation Risk Score Calculator
An unrest score is a weighted summary of evidence under a chosen scoring policy. Missing evidence has its own weight, so the known-evidence score and coverage should be read together.