International Federation of Digital Seismograph Networks

Terms of Reference

The International Seismological Community recognizes the new opportunities within its field for improved understanding of the internal structure and dynamical properties of the Earth provided by seismograph network technology.

It also recognizes that rapid access to seismic data networks of modern broad-band digital instruments wherever they might be is now possible.

The developments include greatly improved broad-band seismographic systems that capture the entire seismic wave field with high fidelity, efficient and economical data communications, vastly improved storage systems, and powerful computing facilities.

The federation is open to all organisations committed to the deployment of broad-band seismographs and organisations involved in management of data from digital seismograph networks, willing to contribute to the establishment of an optimum global system with open and timely data exchange.

I. Goals

In view of the above and to take advantage of existing and developing global and regional networks the “International Federation of Digital Seismograph Networks (FDSN)” provides a forum for:

  • developing common minimum standards in seismographs (e.g. bandwidth) and recording characteristics (e.g. resolution and dynamic range);
  • developing procedures for archiving and exchange of data among component networks and the research and monitoring communities;
  • developing standards for quality control;
  • coordinating the siting of stations in locations that will provide optimum coverage;
  • pursuing free and open access to data;
  • improving access to data in real-time.
  • facilitate capacity building consistent with the goals expressed above

II. Institutional Frame

The Federation is an independent international association and has commission status within the International Association for Seismology and Physics of the Earth’s Interior (IASPEI).

III. Membership and Structure

Membership in the FDSN is open to national and international organisations committed to both the development and operation of the broad-band digital networks as well as organisations involved in management of data from digital seismograph networks consistent with the goals of the Federation. It is required that each network member will contribute digital waveform data, preferably in real time, from a subset of stations in their network to a data center participating in the FDSN Federated Data Center system.
Participation in the FDSN is one of four defined types:

  • Supporting Membership. Supporting membership is open to any network or Data Center that supports the goals of the FDSN and contributes at least $5,000 per year in dues to the FDSN to support the activities and developments of the FDSN.
  • Contributing Membership: Contributing membership is open to any network or Data Center that meets the goals of the FDSN and contributes at $1,000 per year in dues to the FDSN to support the activities and developments of the FDSN.
  • Participating Membership: Participating membership is open to any network that meets the goals of the FDSN.
    Sponsors: Sponsors may be either for profit corporations providing financial or in kind support for FDSN activities or government agencies that provide financial support for key activities undertaken by the FDSN, such as FDSN Data Workshops.

Membership fees are due by January 31 of each year.

The structure of the FDSN includes a steering committee and an executive committee.

The members of the FDSN steering committee will consist of one representative per member organisation who will be appointed or selected from within the organization they represent. Designation of the organisation’s steering committee member must be sent electronically to the FDSN Secretary on the member organisation’s letterhead and signed and dated by an authorized person of the organisation. If a new steering committee representative is selected by an organisation then it is the responsibility of the organisation to inform the FDSN secretary of the change in the same manner as specified in this paragraph.

The members of the FDSN steering committee must approve all new memberships in the FDSN either electronically by email voting or in person at meetings of the FDSN.

The members of the FDSN steering committee elect an FDSN executive committee. The executive committee will coordinate the activities of the Federation between meetings and is responsible for the organization and coordination of the steering committee meetings. Members of the FDSN executive committee are elected for a four-year term.

The FDSN executive committee is headed by a chair, who will be assisted by a secretary and the chairs of all FDSN working groups. The chair of the executive committee will preside over the meetings of the steering committee. Members of the executive committee shall be elected from within the steering committee or the member organizations. Elections take place during steering committee meetings.

The FDSN steering committee will form all necessary working groups or special technical committees as required to achieve the objectives of the FDSN. Each working group or special technical committee is headed by a chair who is supported by a Vice Chair.

The FDSN steering committee will deliberate at least once every two years. Special meetings may be called by the Excom chair as necessary for the progress of the FDSN.

Voting Procedures

At major steering committee meetings held every two years, or other steering committee meetings called by the FDSN Excom chair, votes can only be cast by steering committee members or their designated alternate from the same organization attending the meeting either in person or virtually.

A majority of 2/3 of the votes cast will be required for an affirmative vote. Five members of the FDSN will constitute a quorum for FDSN steering committee meetings.

FDSN Voting on Non-Financial Matters

Concerning all non-financial recommendations made and actions to be taken, each steering committee member will have one vote, regardless of their membership category.

FDSN Voting on Financial Matters

Concerning all FDSN matters of a financial nature including approval of the annual FDSN budget, specific expenditures for which the steering committee might wish to see made, and any other items having a financial impact, voting will be as follows:

  • Supporting Members of the FDSN will have six votes,
  • Contributing Members of the FDSN will have two votes,
  • Participating members of the FDSN will have one vote.

updated 2021-08-23