### Summary

This metric computes the difference between the minimum and maximum sample value (range) in a rolling 300-second window, reporting the largest range value in counts found in a daily 24-hour period.

NOTE: This metric was introduced into MUSTANG in June 2020 and we have just begun calculation of values across the archive. We will continue to fill in values for network-station-channel-days until we achieve complete coverage.

### Uses

This metric can help characterize the largest seismic or noise-related signal over the course of a day, excluding extremely long period signals. This may be useful for identifying stations that have large sensor pings, spikes, or other recurrent signals that, e.g., may potentially cause false STA/LTA triggers in an earthquake early warning system.

### Data Analyzed

**Traces** – one N.S.L.C (Network.Station.Location.Channel) per measurement

**Window** – 24 hours starting at 00:00:00 UTC

**Data Source** – IRIS miniSEED archive or IRIS PH5 archive

**SEED Channel Types** –
?H?, ?L?, ?N?, ?G?, ?P? | High Gain, Low Gain, Accelerometer, Gravimeter, Geophone | excluding very long period channels

### Algorithm

- Request 24 hours of time series data for a single N.S.L.C.
- Fill data gaps with values of NA
- Subset data into 300-second windows with 50% overlap (150 seconds), for a total of 575 data segments.
- For each window, find the maximum and minimum amplitude value:

For i=1,N samples in the time series x: if (x(i) < min) {min = x(i)} if (x(i) > max) {max = x(i)}

- For each window w, calculate the difference between the maximum and minimum amplitude values and store in a vector:

range(w) = max(w)-min(w)

- Identify and report the largest range value for the requested data:

maxRange = maximum(range(w))

### Metric Values Returned

**value** – maximum amplitude range value in counts

**target** – the trace analyzed, labeled as N.S.L.C.Q (Network.Station.Location.Channel.Quality)

**start** – beginning of the data day requested (00:00:00 UTC)

**end** – end of the data day requested (truncated as 23:59:59 UTC)

**lddate** – date/time the measurement was made and loaded into the MUSTANG database (UTC)