An assessment of seismic noise levels for the Advanced National Seismic System backbone network and selected regional broadband stations

In this paper we assess the relative noise levels of 113 broadband seismic stations within the United States Geological Survey’s (USGS) Advanced National Seismic System (ANSS) (netcode US), the Global Seismic Network (GSN) (netcodes II, IU) and several United States regional networks (netcodes CI, LB, UO, UW, NM). This assessment makes use of seismic power spectral data collected by a continuous noise monitoring system developed by the USGS-ANSS and the Incorporated Research Institutions in Seismology (IRIS) Data Management Center (DMC). We rank the stations relative to the Peterson Low noise model (LNM) (Peterson, 1993) for 11 different period bands. Results are listed in Appendix A. Results show that most regional stations rank low in all period bands. In general, stations in the US network have lower noise levels at short periods (0.0625-8.0 seconds), high frequencies (8.0-0.125Hz) while stations in the GSN network are quieter at long periods (16.0-128.0 seconds), low frequencies (0.03125-0.01563Hz). This result reflects the overall mission and objectives of each network.