Noise Performance of IRIS/IDA Broadband Seismic Stations AAK and TLY in the USSR
Abstract
Absolute ground noise levels (power spectral amplitude vs. frequency) were calculated from .001 Hz to 10 Hz for two seismic stations in the USSR deployed by Project IDA in fall of 1990. The stations are located at Ala-Archa, Kirghizia (AAK; lat-42.639 degree N, Ion 74.494 degree E, elev 1645 m) and Talaya, in Siberia (TLY; lat 51.681 degree N,Ion 103.644 degree E, elev 579 m). Findings can be summarized as follows: Station AAK shows the lowest average absolute nighttime noise levels above 1 Hz documented to date for IDA USSR stations. Ground noise increases during the day over night levels at AAK, with the maximum increase (7-9 dB) occuring between 2-3 Hz. Below .7 Hz, day and night noise levels are the same at AAK. TLY average nighttime ground noise levels are about 6-10 dB higher than AAK levels above 1 Hz. Below .6 Hz, nighttime levels at AAK and TLY are comparable, except that TLY has lower horizontal noise levels (4-5 dB) at periods longer than 25 s. Almost no difference between night and day noise levels was observed at TLY; in this sense it is unique among the IDA USSR stations.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 18, 1991
- Accession Number
- ADA246676
Entities
People
- Holly K. Given
Organizations
- Scripps Institution of Oceanography