The character of seafloor ambient noise recorded offshore New Zealand : results from the MOANA ocean bottom seismic experiment
Sheehan, Anne F.
Collins, John A.
MetadataShow full item record
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.
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.
Showing items related by title, author, creator and subject.
Multiproxy analysis of a new terrestrial and a marine Cretaceous–Paleogene (K–Pg) boundary site from New Zealand Ferrow, Embaie; Vajda, Vivi; Koch, Christian Bender; Peucker-Ehrenbrink, Bernhard; Willumsen, Pi Suhr (2010-10-20)An integrated study of palynology, Mössbauer spectroscopy, mineralogy and osmium isotopes has led to the detection of the first K-Pg boundary clay layer in a Southern Hemisphere terrestrial setting. The K-Pg boundary ...
Diversity and biogeochemical structuring of bacterial communities across the Porangahau ridge accretionary prism, New Zealand Hamdan, Leila J.; Gillevet, Patrick M.; Pohlman, John W.; Sikaroodi, Masoumeh; Greinert, Jens; Coffin, Richard B. (2011-07-04)Sediments from the Porangahau ridge, located off the northeastern coast of New Zealand, were studied to describe bacterial community structure in conjunction with differing biogeochemical regimes across the ridge. Low ...
Multibeam bathymetric surveys of submarine volcanoes and mega-pockmarks on the Chatham Rise, New Zealand Collins, John A.; Molnar, Peter H.; Sheehan, Anne F. (2011-04)Multibeam bathymetric surveys east of the South Island of New Zealand present images of submarine volcanoes and pockmarks west of Urry Knolls on the Chatham Rise, and evidence of submarine erosion on the southern margin ...