USGS Professonal Paper 1096 - IRIS

ARKANSAS--Continued
Ti.ing ayste.: Geotech crystal clock checked with WWV
(50-msee tolerance).
Systea response curves: See figure 3, p. 364.
SHORT HISTORY
The LRSH progrsm began in 1960 ss part of the VELA-Uniform project. It continued until 1971, when it was replaced by the
Special Data Collection System prograa which remains active. Work under these programs has been directed towards advancing the
seismic-detection, identification, and location techniques necessary to detect and identify underground nuclear explosions.
All work is accomplished under the technical direction of AFTAC, Vela Seismic Center, in Alexandria, Va.
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