OBC Sensor Response and Calibrated Reflectivity

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2007OBC sensor response and calibrated reflectivityAuthors: Milo M. BackusPaul E. MurrayRobert J. GraebnerBob A. HardageMilo M. BackusExploration Geophysics Laboratory, Bureau of Economic Geology, Jackson School of Geosciences, The University of Texas at AustinSearch for more papers by this author, Paul E. MurrayExploration Geophysics Laboratory, Bureau of Economic Geology, Jackson School of Geosciences, The University of Texas at AustinSearch for more papers by this author, Robert J. GraebnerExploration Geophysics Laboratory, Bureau of Economic Geology, Jackson School of Geosciences, The University of Texas at AustinSearch for more papers by this author, and Bob A. HardageExploration Geophysics Laboratory, Bureau of Economic Geology, Jackson School of Geosciences, The University of Texas at AustinSearch for more papers by this authorhttps://doi.org/10.1190/1.2792582 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract Given deep‐water OBC data, we can combine hydrophone (P) and vertical‐geophone (Z) data to separate upgoing and downgoing acoustic wavefields. By using the downgoing wavefield to estimate the seismic wavelet, we can recover compressional‐wave reflectivity and provide an acoustic impedance log for the near‐seafloor sedimentary section. This procedure requires the calibration of geophone response to hydrophone response with an appropriate matching filter (z2p). P and Z data containing only upgoing energy can be provided in several ways to estimate z2p and p2z filters. Alternatively, the multiple/primary ratio (in the frequency domain) can be used to obtain calibrated reflectivity from the hydrophone alone or from the geophone alone, with no sensor calibration required. We apply these methods to a deep‐water OBC line. We obtain consistent results by all of the methods. By combining low‐frequency (5–70 Hz) z2p filters based on energy arriving before the direct arrival, with high‐frequency (25–180 Hz) z2p filters based on near‐offset reflection data, we can provide broadband (5–180 Hz) calibrated reflectivity and impedance of shallow seafloor sediments.Permalink: https://doi.org/10.1190/1.2792582FiguresReferencesRelatedDetailsCited ByDeep-water subsurface imaging using OBS interferometryOlivier Carrière and Peter Gerstoft4 February 2013 | GEOPHYSICS, Vol. 78, No. 2Wavefield-separation methods for dual-sensor towed-streamer dataAnthony Day, Tilman Klüver, Walter Söllner, Hocine Tabti, and David Carlson20 March 2013 | GEOPHYSICS, Vol. 78, No. 2Dual‐sensor streamer data: Calibration, acquisition QC and attenuation of seismic interferences and other noisesGuillaume Cambois, David Carlson, Craig Jones, Marina Lesnes, Walter Söllner, and Hocine Tabti14 October 2009Improving sensor technology brings a new level of reservoir understandingMasahiro Kamata, Les Nutt, and William Underhill15 December 2008 SEG Technical Program Expanded Abstracts 2007ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 2007 Pages: 3124 publication data© 2007 Copyright © 2007 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished: 14 Sep 2007 CITATION INFORMATION Milo M. Backus, Paul E. Murray, Robert J. Graebner, and Bob A. Hardage, (2007), "OBC sensor response and calibrated reflectivity," SEG Technical Program Expanded Abstracts : 1044-1048. https://doi.org/10.1190/1.2792582 Plain-Language Summary PDF DownloadLoading ...