RSAM Seismic Amplitude Mean Trend Tool

Compute equal-duration mean absolute detrended ground-velocity RSAM windows with clipping diagnostics; inputs share a fixed sample rate/instrument response and output is not magnitude, tremor attribution or eruption diagnosis.

Description

RSAM summarizes absolute seismic amplitude over fixed windows.

RSAM summarizes absolute seismic amplitude over fixed windows. Clipping can bias that summary even when the arithmetic is correct.

When to use RSAM Seismic Amplitude Mean Trend Tool

Use this tool to compute equal-duration mean absolute detrended ground-velocity RSAM windows with clipping diagnostics; inputs share a fixed sample rate/instrument response and output is not magnitude, tremor attribution or eruption diagnosis.

Gather the relevant observations and fitted model parameters. Use the stated units and time basis; keep paired observations aligned.

How to use RSAM Seismic Amplitude Mean Trend Tool and understand its results

Gather the relevant observations and fitted model parameters. Use the stated units and time basis; keep paired observations aligned.
Enter detrendedGroundVelocitySamples, windowSampleCount, instrumentClipMagnitude using the field table and calculation rules, then run the tool.
Read rsamWindowMeans, windowClippedSampleFractions, lastMinusFirstRsam. The explanation below defines the units, signs, ordering and any flags or placeholder values.
If the tool reports an input issue, correct the values and run it again. Apply the stated assumptions when interpreting a successfully returned result.

Input field	Meaning	Value type; see rules below	Requirement
detrendedGroundVelocitySamples	Detrended ground velocity samples	list of number	Required
windowSampleCount	Window sample count	integer	Required
instrumentClipMagnitude	Instrument clip magnitude	number	Required

Use a nonempty sample list divisible by the positive integer window size and a positive clip magnitude. Partition equal windows, average absolute samples and count values at or above clipping. Return last minus first RSAM.^[1]

RSAM = mean(abs(detrended samples)) per window

Units, indexing, boundary conditions and exceptional cases are defined in the calculation rules above.

Output field	Meaning	Value type
rsamWindowMeans	Rsam window means	list of number
windowClippedSampleFractions	Window clipped sample fractions	list of number
lastMinusFirstRsam	Last minus first rsam	number

json

{
  "input": {
    "detrendedGroundVelocitySamples": [
      -1,
      1,
      -2,
      2
    ],
    "windowSampleCount": 2,
    "instrumentClipMagnitude": 3
  },
  "output": {
    "rsamWindowMeans": [
      1,
      2
    ],
    "windowClippedSampleFractions": [
      0,
      0
    ],
    "lastMinusFirstRsam": 1
  }
}

Limitations and assumptions

Samples need a consistent instrument response and rate; this does not identify tremor or estimate earthquake magnitude.

Numbers and computed results must be finite; overflow produces an error. Numeric lists are limited to 100,000 entries; the rules above may require smaller limits. Missing required fields, extra fields, wrong value types and violations of the calculation rules are input errors.

Alternative or Complementary methods

Use Swarm Rate Acceleration Checker: Audit contiguous exposure-normalized swarm counts using midpoint second differences and a large-count independent-Poisson endpoint ratio error; no earthquake clustering correction, missing-detection inference or eruption probability. For a complementary task, use Thermal Camera Hotspot Area Growth Tracker: Track thresholded physical area and temperature-excess area from calibrated thermal pixels; strict threshold equality is excluded, and emissivity/atmospheric correction or mapped coordinates are caller preprocessing.

References

RSAM Seismic Amplitude Mean Trend Tool — tool.io

Similar or alternative tools

Swarm Rate Acceleration Checker
Audit contiguous exposure-normalized swarm counts using midpoint second differences and a large-count independent-Poisson endpoint ratio error; no earthquake clustering correction, missing-detection inference or eruption probability.
Thermal Camera Hotspot Area Growth Tracker
Track thresholded physical area and temperature-excess area from calibrated thermal pixels; strict threshold equality is excluded, and emissivity/atmospheric correction or mapped coordinates are caller preprocessing.