Data collection at the ISC

Introduction

The ISC collects phase readings and other earthquake bulletin data from over 130 agencies around the world. The data must be sent to the ISC in electronic form. Data sent by fax or on paper is not accepted. The data collected by the ISC is primarily sent by email to the data-collection address: seismoisc.ac.uk

Emailed data is parsed to the ISC database using the ISC 'capture' program. It uses a suite of recognition routines to examine each email, including sender, 'Subject' lines and also the attached data or attachment filename, in order to recognise that an email comes from a particular agency. The data is then parsed into the ISC database.

Approximately 90% of all received data is parsed automatically.

All data-collection queries/issues should be addressed to John Eve at: seismoisc.ac.uk

Email consistency

To ensure that data is parsed automatically, it is very important that agencies are consistent with their email address, subject lines and any attachment filenames.

It would be appreciated if agencies would give ISC advance notice (to seismo@isc.ac.uk) that email addresses are going to change. A new email address results in the data having to be parsed manually.

Registering of Stations

Only data from stations within the International Registry of Seismograph Stations may be parsed into the ISC database. New stations may be registered either by filling out the online form or emailing the station data to seismoisc.ac.uk, for the ISC to complete the registration.

If agencies are aware that there is a new station code(s) in their data, they are urged to register the station(s) before sending the data.

It is recognised that many agencies use and report local station codes which are different, in many cases, to the registered station codes. The ISC can accommodate local codes with a list of aliases for an agency. Hence, the registering of a new code does not necessarily mean that an agency has to change its local code in its data files. Please inform the ISC of any local codes that are sent and their equivalent registered code so we can correctly identify the registered station.

The ISC bulletin will only show stations by their internationally registered code and not by their local code.

Bulletins or separate hypocentre/phase files

Where possible, the ISC prefers to receive data in a Bulletin form - with phase readings directly linked to seismic events - rather than sending a list of phase readings with or without a separate list of hypocentre solutions and other parametric information. Data received in a Bulletin form enables the local expertise of the agency to be directly incorporated into the ISC database and Bulletin and is likely to reduce the number of mistakes in the ISC's automated phase-association process that will have to be corrected manually by ISC Bulletin editors.

Where this is not possible the ISC still accepts separate hypocentre and phase files.

Data Formats

There are now a number of well-recognised standard formats for seismic data - ISF/QuakeML/GSE/Nordic. A list of formats, with links to their documentation can be found on the ISC standards page.

Agencies using bespoke formats or old formats like Telex are encouraged to move to one of the standard formats. Agencies with Focal Mechanism data should look at QuakeML, ISF and Nordic formats.

Where it is not possible to move to a standard format for historical or resource reasons, it is important to be consistent in the format that is sent. This is particularly relevant to formats which use tabs and/or spaces between data-columns. If tabs are used, then spaces should not be used and vice-versa.

When a new bespoke format is created, a detailed description of the format should be sent ahead of the real data, in order for a parser to be written.

Indication of event types

It is very helpful to the ISC and important to the seismological community to know the type of an event, whether it is an Explosion/Mining-related/Earthquake/Volcanic event/etc. The major formats enable the type to be incorporated into the data. Otherwise, this information can be conveyed by Comments.

Data selection

We ask agencies to send all available data, regardless of event magnitude, volume of data, etc. This enables our seismologists to get a fuller picture for each event. Moreover, even if an event does not meet ISC criteria for being reviewed by ISC seismologists, the information is valuable to the seismological community and will be made available in the ISC Bulletin.

Amplitudes/Magnitudes

Amplitudes should be named following the convention in the IASPEI standard seismic phase list (i.e. A, AML, AMB, AMS)

Amplitudes and magnitudes should be measured following the IASPEI Standard procedures for magnitude determination, and named and reported to the ISC according to IASPEI standard seismic phase list. Further details can be found in the recommendations published by IASPEI's Working Group on Magnitudes (Magnitude WG)