SAGE Facility MUSTANG metrics Web Service Documentation

This metric shows the continuous time spans encountered within the requested time period, calculated at query time. It processes the times of data availability based on information stored in the rapidly-accessible IRIS SEED and PH5 archive database indexes (ts_index), as returned by the service.iris.edu/fdsnws/availability and the service.iris.edu/ph5ws/availability web services.

The ts_channel_continuity metric is currently a prototype that will eventually become a standard MUSTANG metric.

Data gaps can indicate problems with data transmission configuration or performance, power cycling or other equipment down time, or data loss after transmission. The metric helps to pinpoint where continuous data can be found and can provide a good indication of how gappy the data is and when.

Traces – one N.S.L.C (Network.Station.Location.Channel) per measurement
Window – from start time to the end time of the request
Data Source – IRIS miniSEED archive database time series index (ts_index)

SEED Channel Types – All Time Series Channels

• Request availability web service trace extents for the time duration on each matching N.S.L.C.
  

  total_duration = request_end_time - request_start_time;
  

• For x entries/data segments returned,
  • Calculate length of up-time for each segment:
    

    segdt(x) = endtime(x) – starttime(x)
    

  • Report segdt(x), starttime(x), and endtime(x) when segdt(x) > 0

value – the data up-time in seconds
target – the trace analyzed, labeled as N.S.L.C.Q (Network.Station.Location.Channel.Quality)
start – the start time of the continuous extent (UTC)
end – the end time of the continuous extent (UTC)
lddate – UTC date/time the measurement was made

If the user specified request end date does not include hour:min:sec, then it defaults to 00:00:00.

• Robert Casey