July - September 2004

Contents

Search for New Members
Farewell to Nurcan
The ISC Says Goodbye to the 30 year old Fortran Code
Data Acquisition - An Appeal to Data Contributers
May - August 2002 Bulletin of the ISC
ISC - NEIC - EMSC Coordination
Visitors
Assistance Required

Search for New Members

The ISC team, of currently only 6 people, is integrating the efforts of seismologists who run stations and networks all around the world and provide readings of phase arrivals and amplitudes. The ISC builds on these efforts to locate tens of thousands earthquakes each year with millions of associated readings. Thanks to its efficiency, the ISC is able to carry out its work while making only modest demands on the resources available for seismological work around the world.

This is a quotation from a letter we have sent during 2004 to more than 15 seismological institutions around the world, inviting them to become members of the ISC and to take part in this huge effort of compiling and editing all available parametric data describing the seismic activity of our planet. We are proud to say that, to the best of our knowledge, all operators of seismic stations and networks around the world are contributing their data to the global seismological community, through the ISC. One of the major contributions is the bulletin of the International Data Centre of the Comprehensive nuclear Test Ban Treaty Organization that has been made available to the ISC since 2000. These integrated efforts require man-power and financial resources. We have no doubt that our colleagues, whether they are members or are not yet members of the ISC, appreciate the work and the products that the ISC provides. Yet there is room for many more improvements and provision of additional services to seismologists. Thus, we need you help in convincing heads of institutions, funding government agencies and other funding organizations to increase the financial support to the ISC and to facilitate membership of new institutions. We would also urge you to support small seismological institutions, especially in developing countries and provide them with the funds to become members of the ISC.

The ISC contribution to the seismological community was demonstrated by Avi Shapira to the participants of the 3rd Conference on Continental Earthquakes in Beijing, China (July 2004) and to the participants of the General Assembly of the European Seismological Commission in Potsdam, Germany (attended by Avi Shapira and Dmitry Storchak). We are grateful to the local organising committees of these meetings for the financial support that facilitated our participation. During these meetings we made contact with seismic station operators and discussed data transmission issues and membership.

Farewell to Nurcan

At the beginning of July 2004, Dr. Nurcan Meral Ozel concluded her two-year appointment as a seismologist at the ISC. She has returned to the Kandilli Observatory and Earthquake Research Institute (KOERI) at Bogazici University, Istanbul. Nurcan was a member of the team of editors of the Bulletin of the ISC. Nurcan was able to share her knowledge of Turkish earthquakes and to improve the interaction between ISC and Turkish networks. The ISC statutes require that ISC promotes international exchange for this very reason. In addition, Nurcan co-authored a number of publications as listed in our previous newsletters. Nurcan's son Mehmet, quickly learned English during their stay here and also became a great fan of Harry Potter! We take this opportunity to thank Nurcan, once again, for her important and valuable contribution to the ISC and the seismological community we serve.

The ISC Says Goodbye to the 30 year old Fortran Code

Over the last year Richard Luckett has been writing new programs to be used by the ISC editors to review the ISC Bulletin. Richard has worked together with Dmitry Storchak throughout the design and testing stages of this project. This work has allowed us to put the new ISC location program, ISCloc, into operation. As a result, the old FORTRAN code, which was used with minor alterations for more than 30 years, has been phased out.

The new editing programs were first used by Maiclaire Bolton and Dmitry Storchak for editing the Bulletin for October 2002. The editing programs and associated tools all now interact directly with the database instead of large binary (wtf) files. This brings great advantages to the ISC in terms of code maintenance and flexibility. Already many of the editing tools are more powerful than those used previously because they can easily compare a month with other months or directly access the unreviewed part of a bulletin for cross-checking.

In future many improvements will be possible in every aspect of editing that would have been unattainable while using the old programs and systems. In particular location and event formation operations are now performed by ISCloc, which is a modern, modular program designed to allow easy changes to the algorithms used for location, magnitude calculation, etc. Although all of these algorithms are currently exactly the same as before, the ISC is now in a position to move forward if funding for new development is found.

Major changes in the core of operation are commonly accompanied with finding and correcting errors, making necessary additions to the software and consequently reprocessing the data. As a result, a considerable backlog in the editing of the ISC Bulletin has been accumulated. Taking into account the advantages of the new software, we are confident that this backlog should be recovered when most of the problems are addressed.

Data Acquisition - An Appeal to Data Contributers

Over 120 agencies are actively sending regular seismic data to ISC. We are very grateful for the continuing effort required to collect, format and send us these data. The ISC's data-capture system is largely automatic; most e-mails are recognised, filed away and the data parsed into the database without any human intervention. However, manual intervention is required for the following reasons:

  • Unknown stations, i.e., stations not included in the international station registry;
  • Data format unexpected changes;
  • Data errors;
  • Parser errors;

Dr. Peter Dawson, who is responsible for data acquisition at the ISC, will obviously correct parser errors and data errors that are bound to happen. After all, we are only human. However, the effect of unregistered stations and unexpected changes in the format of the data sent to us can and should be minimised. It would be appreciated if impending format changes were notified by email to seismo@isc.ac.uk before data in the new format is sent to ISC - this allows time to update and test parsers. Of course, the move to standard formats - ISF, GSE and Nordic completely removes this problem and it becomes highly beneficial to all parties. ISC encourages all agencies with bespoke formats to move to standard format ISF (details can be found on the ISC web site www.isc.ac.uk).

The effect of unknown stations can also be reduced. It would be appreciated if agencies would check that their stations are registered in the International Registry. This check can be carried out using the web-page: http://www.isc.ac.uk/IR/index.html. New stations should be registered at the web-page : http://www.isc.ac.uk/IR/reg.html.

ISC maintains a station-mapping file for every agency - this maps all of the station codes used in agency data-files to registered station codes. Whenever a new station code (even if it is already registered) is used in an agency's data-file - their mapping file needs to be updated. Hence, if agencies are aware of new station codes in their data (even if the code(s) are registered) it would also be appreciated if ISC was informed by e-mail, ahead of the actual data being sent to us. These e-mails should be sent separately from the data (to seismo@isc.ac.uk) - otherwise they may be filed away by the automatic data-capture system and not seen.

May - August 2002 Bulletin of the ISC

The second edition of the ISC printed bulletin for 2002 (volume 39) has been produced and distributed. This bulletin encompasses four months of data and contains printed details of the events reviewed and relocated by the ISC seismologists for the months May to August 2002.

The CD-ROM contains the full comprehensive Bulletin in FFB and ISF formats with all phase data included even for the smallest of un-reviewed events, as well as the full reviewed Bulletin in PDF format for each of the four months. For this edition of the Bulletin, 11,280 events were reviewed for which there were 35,616 hypocentres and 565,357 associated phases. The comprehensive Bulletin extends this to 71,530 events, 97,280 hypocentres and 945,600 associated phases.

ISC - NEIC - EMSC Coordination

Remy Bossu, secretary general of the European Mediterranean Seismological Centre has coordinated a joint document of the three data centres that projects the problems faced at the data centres for parametric data from the current practice of coding seismic stations. This issue was further presented at a meeting with the Federation of Digital Broad-Band Seismograph Networks (during the ESC assembly). As a result of these discussions the Secretary-General of IASPEI has approved the establishment of a new Working Group of IASPEI on Seismic Station Code Names. It is expected that other data centres will join these efforts. Avi Shapira will chair this working group and we plan for a joint meeting during the next IASPEI assembly in Santiago de Chile in 2005. This workshop/working group meeting will hopefully foster discussions on other topics that should be coordinated between regional and international data centres, including those dealing with waveform, parametric and strong motion data.


Stuart Sipkin and Avi Shapira at the ISC

Coordination with the National Earthquake Information Centre of the US Geological Survey (NEIC) was further improved when Dr. Stuart Sipkin of NEIC visited ISC in July. We were informed that NEIC is planning to assign greater emphasis to quick reporting of earthquakes. NEIC and ISC will also collaborate on sharing parsers and other software for data processing, analysis and editing, when applicable.

Visitors

ISC welcomed two other visitors during this period. Firstly, Dr Irina Gabsatarova from the Russia Academy of Science who came to discuss how the RAS data contribution to the ISC can be improved and enhanced. Secondly, Dr Michael Pasyanos from Lawrence Livermore National Laboratory who was introduced to the ISC collection and analysis techniques and also gave a talk on his work at LLNL.

Assistance Required

The ISC is trying to enhance its visibility through the newsletters and active participation in international seismological meetings. However, we seek your assistance in telling us about the research done by you or by your colleagues that makes use of the ISC bulletin. Please send to avi@isc.ac.uk the reference where the relevant publication was made. It will significantly assist us in presenting ourselves to potential funding organizations.