Publication Date:
2022-05-26
Description:
Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 13 (2012): Q10011, doi:10.1029/2012GC004201.
Description:
We analyze the characteristics of ambient noise recorded on ocean-bottom seismographs using data from the 2009–2010 MOANA (Marine Observations of Anisotropy Near Aotearoa) seismic experiment deployed west and east of South Island, New Zealand. Microseism and infragravity noise peaks are clear on data recorded on the vertical channel of the seismometer and on the pressure sensor. The noise levels in the infragravity band (〈0.03 Hz) on the horizontal seismometer channels are too high to show the infragravity peak. There is a small difference (~0.25 Hz versus ~0.2 Hz) in microseism peak frequencies between the two sides of the South Island on all three seismic channels. Our results show clear depth dependence between the peak frequency of infragravity waves and the water depth. We find that the product of water depth and wave number at the peak frequency is a constant, koH = 1.5. This relationship can be used to determine the variation of phase and group velocity of infragravity waves with water depth, and the location of the infragravity peak and corresponding noise notch at any water depth. These estimates of spectral characteristics, particularly low noise bands, are useful for future OBS deployments.
Description:
The collection of OBS data was supported by
the National Science Foundation Continental Dynamics program
under grants EAR-0409564, EAR-0409609, and EAR-0409835.
Description:
2013-04-16
Keywords:
New Zealand
;
OBS
;
Continental shelf
;
Infragravity wave
;
Noise
Repository Name:
Woods Hole Open Access Server
Type:
Article
Format:
text/plain
Format:
application/pdf
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