ISC-EHB Bulletin: csv arrivals output

The CSV output for the Arrivals search produces one line per arrival. Click here to load an example.

Each line has 25 fields, which are preformatted and comma separated. Each field is in one of 4 groups:

EVENT, ARRIVAL DATA, ORIGIN DATA, EVENT MAGNITUDE


Group Title Position Description
EVENTEVENTID1-9Unique id number specific to each ISC-EHB event.
ARRIVAL DATAREPORTER11-19Name of the agency that reported the arrival data.
ARRIVAL DATASTA21-25Station name where the arrival was recorded.
ARRIVAL DATALAT27-34Latitude of station.
ARRIVAL DATALON36-44Longitude of station.
ARRIVAL DATAELEV46-42Elevation of station (m).
ARRIVAL DATACHN44-46Channel the arrival was recorded on (e.g. SHZ, BHZ, BHE, etc.).
ARRIVAL DATADIST48-51Epicentral distance (degrees) from the station to the epicentre of the prime origin.
ARRIVAL DATABAZ53-57Back-azimuth - azimuth from the station to the epicentre of the prime origin.
ARRIVAL DATAPHASE59-66Phase name of the arrival determined by the ISC-EHB.
ARRIVAL DATADATE68-77Date of the arrival.
ARRIVAL DATATIME79-89Time of the arrival.
ARRIVAL DATARES91-95Travel-time residual for PHASE. This is computed using the ak135 velocity model.
ARRIVAL DATATDEF97-100Time-defining flag. Set to true if the arrival-time was used in the computation of the prime hypocentre. This is generally only known for ISC computed hypocentres.
ARRIVAL DATAAMPLITUDE102-110Amplitude measurement (nm).
ARRIVAL DATAPER112-116Period (s) used in the amplitude measurement.
ORIGIN DATAAUTHOR118-126Author of the prime hypocentre.
ORIGIN DATADATE128-137Date of the prime hypocentre.
ORIGIN DATATIME139-149Time of the prime hypocentre.
ORIGIN DATALAT151-158Latitude of the prime hypocentre.
ORIGIN DATALON161-169Longitude of the prime hypocentre.
ORIGIN DATADEPTH171-175Depth (km) of the prime hypocentre.
EVENT MAGNITUDEAUTHOR177-185Author of the selected magnitude.
EVENT MAGNITUDETYPE187-192Magnitude type (e.g. Mw, MS, mb, ml, etc. ) of the selected event magnitude.
EVENT MAGNITUDEMAG194-197Magnitude value of the selected event magnitude.

Notes on the event magnitude

As there are potentially many magnitudes for each event, to reduce the size of the output, only a single magnitude is returned per event for the arrival search. To determine the magnitude that is selected, the following logic is used:

  • Only use the magnitude that fulfills the search requirements (e.g. magnitude range, magnitude type, magnitude author).
    • If no author is specified, choose a magnitude associated to the prime hypocentre.
    • If there is more than one magnitude associated to the prime hypocentre, preferentially choose Mw, mb, ms, ml, respectively.
    • Preferentially choose the largest value if any choice remains.
      • If no author is specified and there is no magnitude associated to the prime hypocentre, preferentially choose magnitudes by GCMT/HRVD, NEIC, NIED, JMA, IDC (mb only).
      • If there is more than one magnitude associated to the preferred author, preferentially choose Mw, mb, ms, ml, respectively.
      • Preferentially choose the largest value if any choice remains.
        • If no author is specified and there is no magnitude associated with the prime hypocentre, and there is no magnitude by one of the preferred magnitude authors, preferentially choose Mw, mb, ms, ml, respectively.
        • Choose the largest value if any choice remains.