Estimate of the bottom compressional wave speed profile in the northeastern South China Sea using "Sources of Opportunity"
Lynch, James F.
Newhall, Arthur E.
Schock, Steven G.
Bartek, Louis R.
MetadataShow full item record
The inversion of a broad-band "source of opportunity" signal for bottom geoacoustic parameters in the northeastern South China Sea (SCS) is presented, which supplements the towed source and chirp sonar bottom inversions that were performed as part of the Asian Seas International Acoustics Experiment (ASIAEX). This source of opportunity was most likely a "dynamite fishing" signal, which has sufficient low-frequency content (5-500 Hz) to make it complimentary to the somewhat higher frequency J-15-3 towed source (50-260 Hz) signals and the much higher frequency (1-10 kHz) chirp signals. This low frequency content will penetrate deeper into the bottom, thus extending the other inverse results. Localization of the source is discussed, using both a horizontal array for azimuthal steering and the "water wave" part of the pulse arrival for distance estimation. A linear broad-band inverse is performed, and three new variants of the broad-band inverse, based on: 1) the Airy phase; 2) the cutoff frequency; and 3) a range-dependent medium are presented. A multilayer model of the bottom compressional wave speed is obtained, and error estimates for this model are shown, both for the range-independent approximation to the waveguide and for the range-dependent waveguide. Directions for future research are discussed.
Author Posting. © IEEE, 2004. This article is posted here by permission of IEEE for personal use, not for redistribution. The definitive version was published in IEEE Journal of Oceanic Engineering 29 (2004): 1231-1248, doi:10.1109/JOE.2004.834681.
Suggested CitationIEEE Journal of Oceanic Engineering 29 (2004): 1231-1248
Showing items related by title, author, creator and subject.
The role of magmatism in the thinning and breakup of the South China Sea continental margin: Special Topic: the South China Sea Ocean Drilling Sun, Zhen; Lin, Jian; Qiu, Ning; Jian, Zhimin; Wang, PinXian; Pang, Xiong; Zheng, Jinyun; Zhu, Benduo (Oxford University Press, 2019-08-13)Magmatism plays a key role in the process of continental margin breakup and ocean formation. Even in the extremely magma-poor Iberia and Newfoundland margin, studies of field outcrops have shown that syn-rift magmatism had ...
South China Sea hydrological changes and Pacific Walker Circulation variations over the last millennium Yan, Hong; Sun, Liguang; Oppo, Delia W.; Wang, Yuhong; Liu, Zhonghui; Xie, Zhouqing; Liu, Xiaodong; Cheng, Wenhan (Nature Publishing Group, 2011-04-26)The relative importance of north–south migrations of the intertropical convergence zone (ITCZ) versus El Niño-Southern Oscillation and its associated Pacific Walker Circulation (PWC) variability for past hydrological change ...
Quantitative bedrock geology of east and Southeast Asia (Brunei, Cambodia, eastern and southeastern China, East Timor, Indonesia, Japan, Laos, Malaysia, Myanmar, North Korea, Papua New Guinea, Philippines, far-eastern Russia, Singapore, South Korea, Taiwan, Thailand, Vietnam) Peucker-Ehrenbrink, Bernhard; Miller, Mark W. (American Geophysical Union, 2004-01-17)We quantitatively analyze the area-age distribution of sedimentary, igneous and metamorphic bedrock based on data from the most recent digital geologic maps of East and Southeast Asia (Coordinating Committee for Coastal ...