S-wave Velocity Model Estimation using Ambient Seismic Noise at Virgo, Italy

Abstract

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2017S-wave Velocity Model Estimation using Ambient Seismic Noise at Virgo, ItalyAuthors: Soumen KoleyHenk Jan BultenJo van den BrandMaria BaderXander CampmanMark BekerSoumen KoleyNational Institute of Subatomic PhysicsSearch for more papers by this author, Henk Jan BultenNational Institute of Subatomic PhysicsSearch for more papers by this author, Jo van den BrandNational Institute of Subatomic PhysicsSearch for more papers by this author, Maria BaderNational Institute of Subatomic PhysicsSearch for more papers by this author, Xander CampmanShell Global SolutionsSearch for more papers by this author, and Mark BekerInnoseis B.V.Search for more papers by this authorhttps://doi.org/10.1190/segam2017-17681951.1 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract In this study, we present an analysis of seismic noise recorded at the Virgo gravitational wave detector in Italy. The study originates from the need to understand the spatio-spectral characteristics of the seismic noise at the Virgo site. Studying the direction of propagation and Rayleigh wave phase velocities of possible noise sources is of utmost importance for accurate computation of Newtonian noise, which appears to be the ultimate low frequency limit for ground based gravitational wave detectors. For this purpose, a seismic array was designed that would ensure correct estimation of phase velocities and propagation direction of ambient seismic noise in the frequency range 0.4−8.0 Hz. Consequently, a passive seismic survey was carried out using a network of 5 Hz vertical component wireless geophones at the site between 13-28 August 2016. The 0.2−0.7 Hz frequency band was dominated by the secondary microseismic energy originating from the Mediterranean sea. A strong correlation was observed between the microseismic energy and the significant wave height in the Mediterranean sea during the time. Seismic noise in the frequency band 1.5−4.0 Hz was dominated by ground motions induced in the subsurface by road bridges and local traffic activities. In the 4−8 Hz band, noise sources were mostly local and transient. The direction of propagation of the ambient noise was estimated using beamforming. To estimate the phase velocities, both beamforming and extended spectral autocorrelation (ESAC) were used. Using the derived Rayleigh wave phase velocity corresponding to the fundamental mode, an inversion was carried out to estimate a 1-D S-wave velocity model for the region. Subsurface properties obtained from the study can be further used for computing the gravity gradient noise associated with seismic motions in the region. Presentation Date: Tuesday, September 26, 2017 Start Time: 2:15 PM Location: Exhibit Hall C/D Presentation Type: POSTER Keywords: passive acquisition, surface wave, arrays, near surfacePermalink: https://doi.org/10.1190/segam2017-17681951.1FiguresReferencesRelatedDetailsCited byThe Virgo O3 run and the impact of the environment29 November 2022 | Classical and Quantum Gravity, Vol. 39, No. 23Environmental Noise in Gravitational-Wave Interferometers2 July 2022Environmental Noise in Gravitational-Wave Interferometers23 December 2021Machine learning for gravitational-wave detection: surrogate Wiener filtering for the prediction and optimized cancellation of Newtonian noise at Virgo10 September 2020 | Classical and Quantum Gravity, Vol. 37, No. 19 SEG Technical Program Expanded Abstracts 2017ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 2017 Pages: 6093 publication data© 2017 Published in electronic format with permission by the Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished Online: 17 Aug 2017 CITATION INFORMATION Soumen Koley, Henk Jan Bulten, Jo van den Brand, Maria Bader, Xander Campman, and Mark Beker, (2017), "S-wave Velocity Model Estimation using Ambient Seismic Noise at Virgo, Italy," SEG Technical Program Expanded Abstracts : 2946-2950. https://doi.org/10.1190/segam2017-17681951.1 Plain-Language Summary Keywordspassive acquisitionsurface wavearraysnear surfacePDF DownloadLoading ...