Materials of the International Conference
50th Anniversary of the International Geophysical Year
and Electronic Geophysical Year

16-19 September 2007 • Suzdal, Russia

The International Seismological Centre

Avi Shapira

International Seismological Centre, Thatcham, UK


The International Seismological Centre is a non-governmental, non-profit making organization, charged with the final collection, analysis and publication of earthquake source information from all over the world. Earthquake data are received from more than 100 seismological agencies representing every part of the globe. This data comprises readings from more than 4000 seismograph stations. The ISC builds on the efforts of seismologists who run stations and networks around the world to locate tens of thousands of earthquakes each year. With the current tendency of most local agencies to focus their efforts on rapid dissemination of earthquake information, it is the ISC that becomes the source for the most complete earthquake information. To assure completeness, ISC wait more than a year for all possible earthquake data to be collected before starting to analyze it and to edit the Bulletin. Most of ISC operations are done automatically: Data are collected via the Internet and automatically parsed and inserted into the database. Contributed hypocentres are grouped and phase readings are associated with the automatically selected primary hypocentres. This automatic process is repeated continuously. Many of these events will be relocated by ISC seismologists who manually review every event that complies with one of the following conditions:

– The reported magnitude is higher than 3.5.

– The event has a magnitude greater than 2.5 and was reported by at least 2 agencies.

– The event was recorded at a distance greater than ~1000 km. On the average, about 3500 events with more than 150,000 associated readings are reviewed each month.

In addition to the Bulletin, the ISC provides a number of on-line services among them maintains the International Registry of seismic stations (jointly with USGS/NEIC), provides links to web-sites with additional seismological information, information about seismologists and seismological institutions (national points of contact), bibliography lists, on-line analysis of seismicity information, reports and documentation of ISC's software. Visit for move details.

Citation: Avi Shapira (2007), The International Seismological Centre, in: Materials of the International Conference '50th Anniversary of the International Geophysical Year and Electronic Geophysical Year', GC RAS, Moscow, doi:10.2205/2007-IGY50conf.

© 2007 Geophysical Center RAS and authors