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	Provedor de dados ArchiMer (4) Autor Ardhuin, Fabrice (4) Schimmel, Martin (4) Stutzmann, Eleonore (4) Obrebski, Mathias (2) Farra, Veronique (1) Maggi, Alessia (1) Mangeney, Anne (1) Meschede, Matthias (1) Sergeant, Amandine (1) Mais... Palavra-chave Body waves (1) Compressionnal body waves (1) Double frequency microseism (1) Noise source (1) Noise source spectra (1) Noise sources (1) North Atlantic Ocean (1) Numerical modeling (1) Ocean waves (1) Polarization (1) Secondary microseism (1) Secondary microseisms (1) Site effect (1) Mais... Tipo do documento Text (4) Ano 2017 (1) 2013 (2) 2011 (1) País France (4) Idioma Inglês (4)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 4 Primeira ... 1 ... Última Detection of microseismic compressional (P) body waves aided by numerical modeling of oceanic noise sources ArchiMer Obrebski, Mathias; Ardhuin, Fabrice; Stutzmann, Eleonore; Schimmel, Martin. Among the different types of waves embedded in seismic noise, body waves present appealing properties but are still challenging to extract. Here we first validate recent improvements in numerical modeling of microseismic compressional (P) body waves and then show how this tool allows fast detection and location of their sources. We compute sources at similar to 0.2 Hz within typical P teleseismic distances (30-90 degrees) from the Southern California Seismic Network and analyze the most significant discrete sources. The locations and relative strengths of the computed sources are validated by the good agreement with beam-forming analysis. These 54 noise sources exhibit a highly heterogeneous distribution, and cluster along the usual storm tracks in the... Tipo: Text Palavras-chave: Compressionnal body waves; Noise source; Double frequency microseism; Numerical modeling. Ano: 2013 URL: http://archimer.ifremer.fr/doc/00161/27251/25448.pdf Ocean wave sources of seismic noise ArchiMer Ardhuin, Fabrice; Stutzmann, Eleonore; Schimmel, Martin; Mangeney, Anne. Noise with periods 3 to 10 s, ubiquitous in seismic records, is expected to be mostly generated by pairs of ocean wave trains of opposing propagation directions with half the seismic frequency. Here we present the first comprehensive numerical model of microseismic generation by random ocean waves, including ocean wave reflections. Synthetic and observed seismic spectra are well correlated (r > 0.85). On the basis of the model results, noise generation events can be clustered in three broad classes: wind waves with a broad directional spectrum (class I), sea states with a significant contribution of coastal reflections (class II), and the interaction of two independent wave systems (class III). At seismic stations close to western coasts, noise... Tipo: Text Ano: 2011 URL: http://archimer.ifremer.fr/doc/00044/15531/12926.pdf Frequency-dependent noise sources in the North Atlantic Ocean ArchiMer Sergeant, Amandine; Stutzmann, Eleonore; Maggi, Alessia; Schimmel, Martin; Ardhuin, Fabrice; Obrebski, Mathias. [1] Secondary microseisms are the most energetic waves in the noise spectra between 3 and 10 s. They are generated by ocean wave interactions and are predominantly Rayleigh waves. We study the associated noise sources in the North Atlantic Ocean by coupling noise polarization analysis and source mapping using an ocean wave model that takes into account coastal reflections. From the Rayleigh wave polarization analysis, we retrieve the back azimuth to the noise sources in the time-frequency domain. Noise source modeling enables us to locate the associated generation areas at different times and frequencies. We analyze the distribution of secondary microseism sources in the North Atlantic Ocean using 20 broadband stations located in the Arctic and around the... Tipo: Text Palavras-chave: Noise sources; Secondary microseism; North Atlantic Ocean; Polarization. Ano: 2013 URL: http://archimer.ifremer.fr/doc/00169/28075/26290.pdf The Effect of Water-Column Resonance on the Spectra of Secondary Microseism P-waves ArchiMer Meschede, Matthias; Stutzmann, Eleonore; Farra, Veronique; Schimmel, Martin; Ardhuin, Fabrice. We compile and analyze a dataset of secondary microseismic P-wave spectra that were observed by North American seismic arrays. Two distinct frequency bands, 0.13–0.15Hz and 0.19–0.21Hz, with enhanced P-wave energy characterize the dataset. Cluster analysis allows to classify the spectra and to associate typical spectral shapes with geographical regions: Low frequency dominated spectra (0.13-0.15Hz) are mostly detected in shallower regions of the North Atlantic and the South Pacific, as well as along the Central and South American Pacific coast. High frequency dominated spectra (0.19-0.21Hz) are mostly detected in deeper regions of the North-Western Pacific and the South Pacific. For a selected subset of high quality sources, we compute synthetic spectra... Tipo: Text Palavras-chave: Secondary microseisms; Body waves; Noise source spectra; Ocean waves; Site effect. Ano: 2017 URL: http://archimer.ifremer.fr/doc/00404/51517/52109.pdf Registros recuperados: 4 Primeira ... 1 ... Última

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