17:15 〜 18:30
[STT35-P05] Instrument response calibration of broadband seismometers and velocity-type strong motion sensors in F-net
キーワード：instrument response, calibration, teleseismic surface wave record
Broadband seismometer data are essential for the development of seismological studies such as those investigating earthquake sources and the Earth’s structure. However, previous studies [e.g., Kimura eta l., 2015] have revealed that the metadata describing these data can possibly be contaminated by instrumentation response errors that are often difficult to recognize from visual waveform checks. We have already reported on the development of a method to calibrate the instrumentation responses from ground motions recorded with broadband seismometers in F-net. In this study, we apply this method not only to broadband seismometers but also to velocity-type strong motion sensors in F-net.
To calibrate the instrument responses of seismometers such as the corner period, damping factor, and sensitivity, we have used spectral ratios between teleseismic surface wave records by a broadband seismometer at a target station and those at multiple surrounding reference stations of F-net. At each F-net station, a velocity-type strong motion sensor in addition to a broadband seismometer is installed to extend the dynamic range of the observations. In this study, we add data of the velocity-type strong motion sensors in the calibration analysis. This data addition enabled us to calibrate the response of velocity-type strong motion seismometers. Moreover, we can calibrate the response of broadband seismometers precisely due to the increase of the amount of reference data. We select the strong motion seismometer data whose signal-to-noise ratio is lower than that of broadband seismometers based on noise spectra of background noises.
By systematic evaluation of the seismometer responses, the obtained calibration values will be useful for the various research using the observation data.
To calibrate the instrument responses of seismometers such as the corner period, damping factor, and sensitivity, we have used spectral ratios between teleseismic surface wave records by a broadband seismometer at a target station and those at multiple surrounding reference stations of F-net. At each F-net station, a velocity-type strong motion sensor in addition to a broadband seismometer is installed to extend the dynamic range of the observations. In this study, we add data of the velocity-type strong motion sensors in the calibration analysis. This data addition enabled us to calibrate the response of velocity-type strong motion seismometers. Moreover, we can calibrate the response of broadband seismometers precisely due to the increase of the amount of reference data. We select the strong motion seismometer data whose signal-to-noise ratio is lower than that of broadband seismometers based on noise spectra of background noises.
By systematic evaluation of the seismometer responses, the obtained calibration values will be useful for the various research using the observation data.