G - I
IDA
Project IDA (International Deployment of Accelerometers) is a global array of accelerometers that collects low-frequency seismic data (Agnew, et. al., 1986). This network has been in place since 1975, and has had as many as 18 stations in operation between 1978 to 1987. The original purpose of the network was to collect data for earth structure and earthquake mechanisms, and it has been used to detect slow and silent earthquakes (Beroza and Jordan, 1990). The data from 1978 to 1987 were available, although only 1984 to 1987 were considered carefully because of the sparse global coverage in the earlier years. The stations now have an almost uniform distribution around the globe and respond to frequencies from about one cycle per minute to below one cycle per day. For more information, link to "http://sepwww.stanford.edu/public/docs/sep75/ray1/paper_html/node4.html"