Affiliation:
1. State Key Laboratory of Acoustics, Institute of Acoustics, Chinese Academy of Sciences 1 , Beijing 100190, China
2. Bullard Laboratories, Department of Earth Sciences, University of Cambridge 2 , Cambridge CB3 0EZ, United Kingdom
Abstract
An efficient and precise time-frequency analysis method for real-time ocean bottom seismometer (RTOBS) data in the South China Sea (SCS) is presented. Overcoming the limitations of conventional methods, the method involves temporal segmentation, unique frequency octaves, and Fourier transforms to generate power spectral density (PSD) and probability density function profiles. The method demonstrates superior precision, computational efficiency, and full-bandwidth (0 to Nyquist) capability compared to traditional techniques, as validated through theoretical and empirical evaluations. Applied to SCS RTOBS data, it unveils temporal PSD variations, shedding light on underwater noise sources like earthquakes, offshore blasting, ship-induced disturbances, and tidal effects. Establishing background noise levels in the SCS supports noise source categorization and ocean environment monitoring. Furthermore, comparing onshore and offshore seismic stations advances interdisciplinary research, fostering a comprehensive understanding of acoustics and seismology in the region.
Funder
National Natural Science Foundation of China
Publisher
Acoustical Society of America (ASA)
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