Assessment of Shoulder-Bed, Invasion, and Lamination Effects on Borehole Sonic Logs

dc.contributor.advisorTorres-Verd ́ın, Carlos
dc.creatorPeyret, Aymeric-Pierre Bernard
dc.date.accessioned2020-04-21T02:00:01Z
dc.date.available2020-04-21T02:00:01Z
dc.date.issued2007-05
dc.description.abstractWe quantify the relative effects of shoulder beds, layer thickness, invasion, and sand-shale laminations on monopole and dipole borehole sonic logs. This is accomplished through numerical simulation of sonic waveforms that includes all of the propagation modes within the 1−10kH z range. Numerical simulations assume infinitesimal monopole and dipole sources as well as an array of infinitesimal receivers deployed in close similarity with one commercially available wireline sonic tool. Propagation modes and their velocities are assessed via slowness-time-coherence processing of the simulated waveforms.For the case of shoulder-bed and layer-thickness effects, we consider soft and hard formations bounded by shale layers. The thickness of the formation ischanged to consider cases where transmitter and receivers are completely included in the bed and partially distributed across different beds. Simulations indicate that shoulder- and bed-thickness effects can account for up to 33% variations in theP-wave velocities measured with a monopole source and 31% in the measured S-wave velocities measured with a dipole source compared to those measured across infinitely thick beds.We reproduce the sonic response of sand-shale laminated formations by in-cluding thin shale layers within pay sands. The thickness of shale layers is varied to consider the effect of proportion of sand and shale on the measurements. Simula-tions indicate that shale laminations can account for up to 16.4% variations in the P-velocities measured with a monopole source and up to 3.6% variations in the S-velocities measured with a dipole source with respect to those of effective lamination velocities. Effects of invasion are simulated for the case of water-base mud invading oil-bearing formations. Our simulations indicate that P-wave sonic logs can undergoup to 13% variations due to invasion under realistic assumptions of petrophysical and elastic properties of soft and hard formationsen_US
dc.description.departmentPetroleum and Geosystems Engineeringen_US
dc.format.mediumelectronicen_US
dc.identifier.urihttps://hdl.handle.net/2152/80744
dc.identifier.urihttp://dx.doi.org/10.26153/tsw/7759
dc.language.isoengen_US
dc.relation.ispartofUT Electronic Theses and Dissertationsen_US
dc.rightsCopyright © is held by the author. Presentation of this material on the Libraries' web site by University Libraries, The University of Texas at Austin was made possible under a limited license grant from the author who has retained all copyrights in the works.en_US
dc.rights.restrictionRestricteden_US
dc.subjectSonic logen_US
dc.subjectmonopoleen_US
dc.titleAssessment of Shoulder-Bed, Invasion, and Lamination Effects on Borehole Sonic Logsen_US
dc.typeThesisen_US
dc.type.genreThesisen_US
thesis.degree.departmentPetroleum and Geosystems Engineeringen_US
thesis.degree.disciplinePetroleum Engineeringen_US
thesis.degree.grantorUniversity of Texas at Austinen_US
thesis.degree.levelMastersen_US
thesis.degree.nameMasters of Science in Engineeringen_US

Access full-text files

Original bundle

Now showing 1 - 1 of 1
No Thumbnail Available
Name:
Thesis.2007.Peyret_Aymeric_Pierre.pdf
Size:
2.06 MB
Format:
Adobe Portable Document Format
Description:
Restricted to UT Austin EID holders

License bundle

Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.64 KB
Format:
Item-specific license agreed upon to submission
Description: