VLF propagation loss to a buried seismometer

Author

Sereno, Thomas J. ; Farrell, William E. ; Orcutt, J.A. ; Adair, Richard G.

Author_Institution

Sci. Applications Int. Corp., La Jolla, CA, USA

Volume

13

Issue

4

fYear

1988

fDate

10/1/1988 12:00:00 AM

Firstpage

254

Lastpage

262

Abstract

The propagation loss from a shallow underwater explosion to a buried vertically polarized seismometer over the frequency band between 3 and 15 Hz was measured during the 1983 Ngendei Experiment. The data was recorded in 5.5-km-deep water in the southwest Pacific with a triaxial borehole seismograph emplaced 50 m within the basaltic basement. It is found that the average power decays as r^-3 (r is slant range) beyond 30 km and that the propagation loss is minimal between 6-9 Hz. At shorter ranges, the propagation loss is more complicated and exhibits a stronger frequency dependence. Power in the first water wave is estimated for both buried and ocean-bottom sensors. The ocean-bottom power is approximately 7 dB higher than that recorded by the buried sensor, and both exhibit similar decay rates

Keywords

acoustic wave propagation; oceanography; seismology; seismometers; underwater sound; 3 to 15 Hz; 5.5 km; OBS; VLF propagation loss; basaltic basement; buried seismometer; decay rates; explosion seismology; ocean bottom seismometer; ocean-bottom sensors; shallow underwater explosion; southwest Pacific; triaxial borehole seismograph; underwater sound; Acoustic measurements; Acoustic propagation; Acoustic sensors; Explosions; Extraterrestrial measurements; Frequency; Geophysical measurements; Oceans; Propagation losses; Sea measurements;

fLanguage

English

Journal_Title

Oceanic Engineering, IEEE Journal of

Publisher

ieee

ISSN

0364-9059

Type

jour

DOI

10.1109/48.9238

Filename

9238