About the bulletin search

Use this search to output all available data within the ISC Bulletin. This includes access to prime (preferred) and secondary hypocentres, magnitude values, phase data and moment tensor solutions.

Database

• Reviewed ISC Bulletin:

A subset of the ISC Bulletin that has been manually reviewed by ISC analysts. This includes all events that have been relocated by the ISC. For more information on the Reviewed ISC Bulletin, see here.

• ISC Bulletin:

The entire ISC Bulletin from both reviewed and unreviewed events. This includes the most recent events, which have yet to be reviewed.

Output format

• ISF Bulletin:

The IASPEI Seismic Format (ISF) is a fixed format bulletin. Further information about the different versions of the format and links to the full documentation can be found on the ISF page.

• QuakeML:

QuakeML is an XML representation of seismological data. Data are output as an XML stream using the QuakeML XML Schema, version 1.2. QuakeML has some significant advantages in readability for computers, due to the availability of XML parsers. The format also allows for a distinction to be made between 'picks' provided to the ISC, and 'arrivals', which are picks the ISC has associated to the prime hypocentre. This output is not designed for use in a browser and will cause browsers to crash for large queries. Guidance for constructing URLs to access data in QuakeML is provided on the ISC web services page. For a complete explanation of the schema, please view the documentation on the QuakeML site.

Search region

There are four possible methods for defining a search region (rectangular, circular, global, Flinn-Engdahl region). Leaving fields blank, will automatically default to a global search. To interactively define a search region, using customised shapes, please use the interactive search page. The defined region is used to check only the prime hypocentre - secondary hypocentres within a search region will not influence the results.

Time period

This is the start and end date to search for events. Only the prime hypocentre will be searched to match events - i.e. origin times for secondary hypocentres will not influence the results.

Unknown depths

As some events have no determined depth, you may optionally choose to include events with unknown depths in the search. This will return events which match any selected depth constraint you enter as well as events with no depth.

Unknown magnitudes

As some events have no determined magnitude, you may optionally choose to include events with unknown magnitude values in the search. This will return events which match any selected magnitude constraint you enter as well as events with no magnitude value.

Magnitude type

Limit events by magnitude for specific magnitude types. Due to the large number of magnitude types and the various notation used, the selected type will search all magnitudes of that type. E.g. MB will match all body-wave magnitudes: mb, mB, MB, mb1mx, etc.

Magnitude author

Limit events by magnitude values determined by a specific author. ISC, NEIC, GCMT/HRVD and JMA amongst others are considered reliable magnitude authors. The default uses 'Any', which will match any author that has a magnitude for both prime and secondary hypocentres included in an event. Selecting 'prime author' will limit the search to magnitudes directly associated with the prime hypocentre (usually the same author as the prime hypocentre) - i.e. for events with an ISC authored prime hypocentre, selecting 'Prime author', will limit events to those with ISC determined magnitudes (and any min/max value specified).

Please note: selecting either GCMT or HRVD, will search magnitudes from both of these agencies, as GCMT is a continuation of HRVD.

Defining phases

Defining phases are travel-times, which have been used in the computation of a hypocentre. For events without an ISC authored hypocentre, the number of defining phases is generally unknown. You may optionally choose to include events where the number of defining phases for the prime hypocentre is unknown. This only applies if you have specified a minimum or maximum number of defining phases.

Only output Prime hypocentres

Multiple hypocentres from multiple agencies (E.g. NEIC, IDC, GCMT (centroids)) are contained within the ISC Bulletin for a particular event. The prime hypocentre is the preferred solution. For events with an ISC determined hypocentre, this always be prime. You may optionally limit the output to only show the prime hypocentres. This will also limit magnitudes to those associated to the prime hypocentre.

Output phases

This includes phase data in the output. Phase data includes any arrival-times, amplitudes, station magnitudes, flags for defining phases and travel-time residuals. The size of the output will be significantly increased by outputting phases.

Output magnitudes

This includes network magnitude data in the output.

Output weblinks

This includes any available links for the event such as a link to the full Bulletin output, a link to form a waveform request and any external links. There are also links for each agency to provide their full details.

Output headers

This includes a header with a unique ID number and the geographic region for each event.

Output comments

This outputs all comments, which include focal mechanism solutions for ISF.