114. National Seismograph Network (1971)

National Seismograph Network

The decision to establish a national seismograph network of standardized seismographs in Canada was partially an outgrowth of seismic monitoring done during the 1957-1958 International Geophysical Year (IGY). It was also strongly influenced by Canada’s desire to contribute to the International Monitoring System of the Comprehensive Nuclear Test-Ban Treaty.

Three component (north-south, east-west, and up-down) short-period and long-period instruments were established at what were called standard stations to record the broad range of periods of earthquake-generated seismic waves. Additional short-period vertical stations called regional stations were added in areas of more frequent earthquake activity.

The short-period seismometers were a new lightweight instrument called a Willmore Mark II, and the long-period instruments were a version of ones originally developed at Columbia University. These instruments were vastly superior to the previous instruments deployed in Canada.

The standard station deployed in the new national network was based on the instrumentation used at Resolute, NWT during the 1957-1958 IGY. The network was more or less completed as envisaged with the installation of regional stations in 1971. The Geological Survey of Canada is responsible for managing the network as part of its seismology program.

Category: Equipment and Instrumentation

Decade: 1970s

References

Willmore, P.L., 1960. The new seismograph station at Resolute Northwest Territories; Publications of the Dominion Observatory, v. 24, p. 99–111.

Horner, R.B., Milne, W.G., and McMechan, G.A., 1976. Canadian Earthquakes – 1971; Energy, Mines and Resources Canada, Seismological Series of the Earth Physics Branch, 74; 45 p.

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