• USGS
  • NSF
  • Iris
  • Iris

Project IDA Background

Project IDA (International Deployment of Accelerometers) is a global network of broadband seismometers operated by the Cecil H. and Ida M. Green Institute of Geophysics and Planetary Physics at the Scripps Institution of Oceanography, University of California, San Diego.  IDA is an element of the IRIS / USGS Global Seismographic Network (GSN) financially supported by the US National Science Foundation and the Cecil and Ida Green Foundation for Earth Science. There are currently 40 broadband stations deployed worldwide.

The current GSN consists of two major parts:  IDA operates approximately one-third of the153 stations and the USGS' Albuquerque Seismological Laboratory operates the remainder.  The two organizations use common instrumentation and operational practices.

GSN data may be used for diverse purposes.

Tsunami Warning: When large earthquakes occur at sea, they may generate very large seismic sea waves which pose great danger to many persons around the world who live in coastal communities. Prompt transmission of the seismic data permits experts to locate earthquakes quickly, assess the likelihood they have generated a tsunami, and predict when the destructive wave will arrive. Such predictions have already saved numerous lives. Visit the International Tsunami Information Center for more information.

Emergency Response: Prompt and accurate location of earthquakes allows emergency personnel to better plan their response to disasters that occur in remote regions of the world. Visit the USGS National Earthquake Information Center for more information.

Monitoring Underground Explosions: Seismic methods are used increasingly to monitor adherence to nuclear test ban treaties. When a nuclear device is exploded underground, the resulting shock wave can be detected by seismic instruments over great distances. Some IRIS/IDA seismic stations form part of the network used by the United Nations' Comprehensive Test Ban Treaty Organization to monitor compliance with nuclear test ban treaties.


Project IDA began in 1975 with seed funding from the Green Foundation for Earth Science to create a global network of long period seismometers of an advanced design and based on the La Coste gravimeter widely used in geophysical exploration work.  The network of 15 stations operated from 1975 until 1995.  Data from these original instruments can be obtained from the IRIS Data Management System under network code ID.  Data from the current network are distributed under code II.

The Principal Investigator of Project IDA is Dr. Jonathan Berger and the Executive Director is Dr. Peter Davis.