FIELD STUDY OF VARIATION IN CHARACTERISTICS OF SEISMIC NOISE AND SIGNALS WITH GEOLOGIC AND GEOGRAPHIC ENVIRONMENT
Abstract
A two-year study was conducted to determine relationships among seismic noise, teleseismic signals, and various geologic and geographic recording environments. Variation in seismic noise and signal with geologic- geographic recording environment was measured in California, the Pacific Northwest and in the Appalachian Mountains - Atlantic coastal plain areas, between March 1961 and September 1962. One centrally located station remained fixed, recording simultaneously with another roving station which consecutively recorded in locations of varying geologic and topographic environment. At both stations signal and noise was recorded on film and magnetic tape by tripartite arrays of 4 short-period and 1 long-period vertical seismometers. Noise data gathered was processed by power spectrum analysis to define the noise amplitude spectrum at each recording station. Some cross-spectrum analysis was done on Pacific Northwest data in order to study noise source directions, coherency and phase velocities. Variations in noise and teleseismic signals were then correlated with variations in geologicgeographic recording environment, and conclusions were drawn.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 15, 1963
- Accession Number
- AD0296938
Entities
People
- J.n. Griffin