Investigation of the Signal Enhancement and Discrimination Capabilities of the Intermediate Period Strain-Pendulum Seismograph Combination at HNME (Houlton, Maine)
Abstract
The intermediate period strain-pendulum combination at HNME is very effective in reducing 4-8 second microseisms and enhancing body phases. The spectra and the relative excitation of intermediate period P and S waves show good potential as discriminants between earthquakes and explosions. If, however, discrimination can be made using 1 and 20 second information, then standard instruments have a lower threshold. The spectral behavior of body and surface waves is sensitive to the local structure, and knowledge of the local structure is needed for the refinement of signal processing methods for strain- pendulum combinations. If such knowledge is not available the best method is to design a processor on the basis of noise characteristics alone. Restricting the processor filter to be one-sided relative to zero lag time (physically realizable) degrades the filter performance relative to the two-sided filters but not significantly.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 27, 1972
- Accession Number
- AD0756892
Entities
People
- Zoltan A. Der
Organizations
- Teledyne Technologies