This service queries a database of power spectral densities (PSDs) calculated over one-hour segments. Individual PSDs are aggregated to show the probability distribution of seismic noise levels. PSDs are calculated with the method described by McNamara in 2004 using ObsPy for a particular network/station/location/channel combination.
|/value||Extraction of values as text|
|/availability||Extraction of the periods for which PSDs are available|
How it works
- When a request is made to the PPSD WebService, it is parsed and passed to the SeedPSD exploitation engine.
- SeedPSD extracts the metadata for the target (NSLC) from the inventory.
- SeedPSD extracts from the database the statistical values corresponding to this target over the requested period (start/end)..
- SeedPSD initializes a PPSD object from these values.
- SeedPSD uses this PPSD object to generate an image configured according to the options specified in the request parameters.
- SeedPSD sends the generated image to the client (browser, CLI, ...) that made the request.
- When integrating a MiniSEED file in the Resif-DC data center (Node B), the file is transmitted to the SeedPSD ingestion engine.
- SeedPSD checks the availability and consistency of the metadata corresponding to the file.
- SeedPSD initializes a PPSD object from the content of the MiniSEED file.
- SeedPSD extracts and stores in database the main statistical values calculated by PPSD.
- When integrating a StationXML file in the Resif-DC data center (Node B), each epoch (NSLC start/end) it contains is transmitted to the SeedPSD ingestion engine.
- SeedPSD extracts the metadata related to this era from the inventory.
- SeedPSD extracts and stores in database the main values allowing to identify metadata changes (instrumental response, sampling rate, ...)
- When metadata are already present in the database, SeedPSD compares them with the new ones before inserting them and, in case of discrepancy, invalidates any statistics calculated from them.
|db_bins||(- 200, - 50, 1.0)|