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Ker, Stephan; Le Gonidec, Yves; Gibert, Dominique. |
A wavelet-based method was presented in a previous work to introduce multiscale seismic attributes for high-resolution seismic data. Because of the limited frequency bandwidth of the seismic source, we observed distortions in the seismic attributes based on the wavelet response of the subsurface discontinuities (Le Gonidec et al.). In this paper, we go further in the seismic source-correction by considering L´evy alpha-stable distributions introduced in the formalism of the continuous wavelet transform (CWT). The wavelets are Gaussian derivative functions (GDF), characterized by a derivative order. We show that a high-resolution seismic source, after a classical signature processing, can be taken into account with a GDF. We demonstrate that in the... |
Tipo: Text |
Palavras-chave: Wavelet transform; Wave propagation; Acoustic properties. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00090/20155/17828.pdf |
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Ker, Stephan; Le Gonidec, Yves; Marie, Louis; Thomas, Yannick; Gibert, Dominique. |
Seismic Oceanography is coming of age as an established technique of observation of the thermohaline structure of the ocean. The present paper deals with the seismic reflectivity of the Armorican Shelf seasonal thermocline, west of France, based on two seismic experiments performed with a sparker source. The peak frequency was 500 Hz for the ASPEX experiment, where the thermocline was located at 27 m water depth, and reduced to 400 Hz associated to a higher source level for the IFOSISMO experiment, where the thermocline was 12 m deeper. Despite this settings, only the first experiment could clearly highlight the thermocline reflector, providing the first seismic observation of a shallow oceanic structure. To better understand the limitation of... |
Tipo: Text |
Palavras-chave: Thermocline; Seismic method; Wavelet analysis; Acoustic. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00254/36535/35066.pdf |
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