A note on the effect of bottom currents on an ocean bottom seismometer

Anne M. Trehu

doi:10.1785/bssa0750041195

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A note on the effect of bottom currents on an ocean bottom seismometer

Anne M. Trehu

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Abstract

Two three-component ocean bottom seismometers and a current meter were deployed a few hundred meters apart on the southern Blake Plateau off the United States eastern coast to study the effect of near-bottom currents on the background noise level of seismometers. Although analysis of the data is limited somewhat by instrumental problems, the increase in current speed, which ranged from 2 to 25 cm/sec, is correlated with a broadband increase in the noise level at frequencies below 10 Hz. Intermittent periods of narrow-band 8-Hz noise, which were also observed, are not correlative with bottom currents and were tentatively attributed to passing ships. Details of the mechanism of generation of the background noise cannot be determined from the present data set.

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Bulletin of the Seismological Society of America Article

Source-reported bounding extent: 30.06909396443887° to 32.58384932565662° latitude; -81.8701171875° to -76.9921875° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Anne M. Trehu. 1985. A note on the effect of bottom currents on an ocean bottom seismometer. https://doi.org/10.1785/bssa0750041195

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