Abstract
The records of ground motion, measured by broadband seismometers, serve for a wide range of scientific research activities. Accordingly, the knowledge of key parameters of seismometers is important for providing reliable results. In most common quality control procedures, the tested seismometer is installed side by side with the reference seismometer. Then, a three-dimensional matrix transforming recordings from one unit to another is needed. The quality of a design of this transformation matrix depends on the mathematical background of a chosen procedure, on the quality of a recorded seismic signal, and on the used bandwidth. In this paper, we present five different mathematical techniques to calculate transformation matrices. One of these techniques is applied in the time domain while the four others use the frequency domain. The methods were verified by two different cases, where different pairs of seismometers were installed on different locations. In all cases, the procedure, reducing the “average” self-noise gives the best result, regards to the decision criteria.
Abbreviations
- BB:
-
Broadband
- PSD:
-
Power spectral density
- CPSD:
-
Cross-power spectral density
- 3D:
-
Three dimensional
- A/D:
-
analog-to-digital converters
- TD:
-
Time domain
- PE:
-
Power equalization
- CP:
-
Coherent power
- ASN:
-
Average self-noise
- SSN:
-
Single self-noise
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Acknowledgments
We thank the Slovenian Environment Agency (ARSO) to enable the measurements and the Central Institute for Meteorology and Geodynamics (ZAMG) for seismic data from the Conrad Observatory in Austria. The authors would like to express their gratitude to both anonymous reviewers for their constructive and useful comments and advices.
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Tasič, I., Runovc, F. The development and analysis of 3D transformation matrices for two seismometers. J Seismol 18, 575–586 (2014). https://doi.org/10.1007/s10950-014-9429-0
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DOI: https://doi.org/10.1007/s10950-014-9429-0