The influence of uncertainties in anisotropy on structural uncertainties

Abstract

PreviousNext No AccessSEG Technical Program Expanded Abstracts 2004The influence of uncertainties in anisotropy on structural uncertaintiesAuthors: Kenneth P. BubeTamas NemethOleg MikhailovDon MedwedeJonathan A. KaneKenneth P. BubeUniversity of Washington, Seattle, WASearch for more papers by this author, Tamas NemethChevronTexaco, San Ramon, CASearch for more papers by this author, Oleg MikhailovChevronTexaco, San Ramon, CASearch for more papers by this author, Don MedwedeChevronTexaco, San Ramon, CASearch for more papers by this author, and Jonathan A. KaneMIT, Cambridge, MASearch for more papers by this authorhttps://doi.org/10.1190/1.1851210 SectionsAboutPDF/ePub ToolsAdd to favoritesDownload CitationsTrack CitationsPermissions ShareFacebookTwitterLinked InRedditEmail Abstract Errors in the velocity field used to migrate seismic data are a leading cause of errors in the positionining of structural events in the processing of seismic data: uncertainty in the velocity field leads to structural uncertainty. In this paper, we study the errors in the positioning of structural events caused by using an isotropic migration code when the true subsurface is TTI and weakly anisotropic. We perform a sensitivity analysis, obtaining simple formulas for the errors in structure that are first‐order in Thomsen's (1986) anisotropic parameters δ and ε. Being the result of sensitivity analysis, these formulas are linear. Thus if we had a probability distribution for the anisotropic parameters δ and ε (i.e., we knew the uncertainty in δ and ε), we could use these formulas to obtain a probability distribution for the errors in position for points on the selected event (i.e., the uncertainty in structure). The formulas simplify greatly when the true subsurface is weakly anisotropic and either TTI and elliptical, or VTI. Our analysis focuses on the neighborhood of a single point on an event and assumes a homogeneous TTI velocity field. We use results from a companion paper (Bube et al., 2004), which investigates how errors in stacking velocity, time to an event in a stacked section, and the slope of an event in a time section lead to errors in the positioning of structural events for an isotropic medium; all three of these enter into our analysis for weakly anisotropic media.Permalink: https://doi.org/10.1190/1.1851210FiguresReferencesRelatedDetailsCited byStructural Uncertainty Analysis using 3D Seismic and Well Data to Estimate Gross Rock Volume GRV Ranges in Reservoir: A Case Study in Carbonate Reservoir, UAE13 November 2017The effect of velocity uncertainty on migrated reflectors: Improvements from relative-depth imagingOleg V. Poliannikov and Alison E. Malcolm6 November 2015 | GEOPHYSICS, Vol. 81, No. 1The influence of stacking velocity uncertainties on structural uncertaintiesKenneth P. Bube, Jonathan A. Kane, Tamas Nemeth, Don Medwede, and Oleg Mikhailov3 January 2005 SEG Technical Program Expanded Abstracts 2004ISSN (print):1052-3812 ISSN (online):1949-4645Copyright: 2004 Pages: 2586 publication data© 2004 Copyright © 2004 Society of Exploration GeophysicistsPublisher:Society of Exploration Geophysicists HistoryPublished Online: 03 Jan 2005 CITATION INFORMATION Kenneth P. Bube, Tamas Nemeth, Oleg Mikhailov, Don Medwede, and Jonathan A. Kane, (2004), "The influence of uncertainties in anisotropy on structural uncertainties," SEG Technical Program Expanded Abstracts : 2192-2195. https://doi.org/10.1190/1.1851210 Plain-Language Summary PDF DownloadLoading ...