Mud and casing effects on borehole crossdipole flexural wave dispersion subjected to stress-induced anisotropy

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2017Mud and casing effects on borehole crossdipole flexural wave dispersion subjected to stress-induced anisotropyAuthors: Yunfei YangMehdi E. FarKristoffer WalkerChung ChangJohn GranvilleBrian HornbyYunfei YangStanford UniversitySearch for more papers by this author, Mehdi E. FarHalliburtonSearch for more papers by this author, Kristoffer WalkerHalliburtonSearch for more papers by this author, Chung ChangHalliburtonSearch for more papers by this author, John GranvilleHalliburtonSearch for more papers by this author, and Brian HornbyHalliburtonSearch for more papers by this authorhttps://doi.org/10.1190/segam2017-17539919.1 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract Wireline sonic tools can sense radial profiling of rock velocities and elastic constants near a borehole by measuring the borehole response to dipole sources. In particular, dispersion curves of flexural waves excited by such sources are sensitive to several factors: the intrinsic anisotropy of rock formations, stress concentrations near the borehole, inhomogeneities in the surrounding media (e.g., invaded zones, casing, etc.), and elastic property contrast between the solid (rock and/or casing) and the fluid (mud). This paper presents several forward modeling cases in which the mud and casing effects on the cross-dipole flexural wave dispersion behavior is studied in the context of measurement of horizontally transverse isotropic (HTI) anisotropy. It is observed that stress-induced anisotropy indicators, such as cross-overs in dispersion curves resulting from the differences between near-borehole and deep formation anisotropies, can be influenced by mud properties and the presence of casing. Therefore, inclusion of these influences in advanced inversion algorithms will yield more accurate anisotropy measurements. Presentation Date: Wednesday, September 27, 2017 Start Time: 9:20 AM Location: 362D Presentation Type: ORAL Keywords: acoustic, anisotropy, logging, borehole geophysics, dispersionPermalink: https://doi.org/10.1190/segam2017-17539919.1FiguresReferencesRelatedDetailsCited byAn analytical approach for cased borehole stress calculation in general anisotropic formations5 August 2020 | International Journal for Numerical and Analytical Methods in Geomechanics, Vol. 45, No. 1 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 Yunfei Yang, Mehdi E. Far, Kristoffer Walker, Chung Chang, John Granville, and Brian Hornby, (2017), "Mud and casing effects on borehole crossdipole flexural wave dispersion subjected to stress-induced anisotropy," SEG Technical Program Expanded Abstracts : 854-859. https://doi.org/10.1190/segam2017-17539919.1 Plain-Language Summary Keywordsacousticanisotropyloggingborehole geophysicsdispersionPDF DownloadLoading ...