Summary
The SH body-wave spectrum of a deep earthquake, which occurred at the foot of the Kamchatka peninsula and was recorded in the Solomon Islands, presents a regular modulation.
The distribution of minima in the amplitude spectrum, corresponding to jumps in the phase spectrum, conforms with that expected from the interference between direct and surface reflected waves.
The strong dependence of the modulation on the focal depth, emerging from theoretical SH body wave spectra obtained with the contribution of the first 21 higher Love-wave modes, was used to investigate the focal depth of the event here considered. The value estimated, 140 km, agrees with an earlier focal depth determination by travel time data.
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Mantovani, E., Gasperini, P. Focal depth information from the SH body wave spectrum of a deep earthquake. PAGEOPH 118, 1234–1247 (1980). https://doi.org/10.1007/BF01593065
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DOI: https://doi.org/10.1007/BF01593065