dc.contributor.author | Song, Ruolong | |
dc.contributor.author | Dong, Hefeng | |
dc.contributor.author | Bao, Xueshan | |
dc.date.accessioned | 2019-11-28T14:56:29Z | |
dc.date.available | 2019-11-28T14:56:29Z | |
dc.date.created | 2019-11-11T14:17:41Z | |
dc.date.issued | 2019 | |
dc.identifier.citation | Geophysics. 2019, 84 (4), D171-D177. | nb_NO |
dc.identifier.issn | 0016-8033 | |
dc.identifier.uri | http://hdl.handle.net/11250/2630942 | |
dc.description.abstract | Cement-bond evaluation is needed for new wells and plug and abandonment activities. The ultrasonic leaky Lamb-wave (also called the flexural-wave) technique, in combination with the pulse-echo technique, has been widely used for cementquality evaluation. Using a 2D time-domain staggered-grid stress-velocity finite-difference methodology, we have numerically investigated the attenuation and group velocity of flexural waves, and the scattering from defects, in the presence of a water-filled void in the cement annulus. The position, length, thickness, and burial depth of a defect are considered. The numerical study suggests that the combination of the attenuation and group velocity of the flexural wave allows for a discrimination between solids and liquids. The scattering from voids can be used to indicate the existence of a hidden defect, which cannot be detected by using the attenuation and group velocity if it is located larger than 5 mm away from the casing. The void signatures can even be used to characterize the geometry of the defect for neat cement. The numerical results provide improved understanding of flexural-wave logging results. | nb_NO |
dc.language.iso | eng | nb_NO |
dc.publisher | Society of Exploration Geophysicists | nb_NO |
dc.title | Numerical study of the effect of cement defects on flexural-wave logging | nb_NO |
dc.type | Journal article | nb_NO |
dc.type | Peer reviewed | nb_NO |
dc.description.version | publishedVersion | nb_NO |
dc.source.pagenumber | D171-D177 | nb_NO |
dc.source.volume | 84 | nb_NO |
dc.source.journal | Geophysics | nb_NO |
dc.source.issue | 4 | nb_NO |
dc.identifier.doi | 10.1190/GEO2018-0464.1 | |
dc.identifier.cristin | 1746096 | |
dc.relation.project | Norges forskningsråd: 237887 | nb_NO |
dc.description.localcode | Use is subject to SEG terms of use and conditions. | nb_NO |
cristin.unitcode | 194,63,35,0 | |
cristin.unitname | Institutt for elektroniske systemer | |
cristin.ispublished | true | |
cristin.fulltext | original | |
cristin.qualitycode | 2 | |