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dc.contributor.advisorAlkhalifah, Tariq Ali
dc.contributor.authorDjebbi, Ramzi
dc.date.accessioned2017-10-25T07:16:27Z
dc.date.available2018-10-25T00:00:00Z
dc.date.issued2017-10-24
dc.identifier.doi10.25781/KAUST-QD4SH
dc.identifier.urihttp://hdl.handle.net/10754/625938
dc.description.abstractThe main goal in seismic exploration is to identify locations of hydrocarbons reservoirs and give insights on where to drill new wells. Therefore, estimating an Earth model that represents the right physics of the Earth's subsurface is crucial in identifying these targets. Recent seismic data, with long offsets and wide azimuth features, are more sensitive to anisotropy. Accordingly, multiple anisotropic parameters need to be extracted from the recorded data on the surface to properly describe the model. I study the prospect of applying a scattering integral approach for multi-parameter inversion for a transversely isotropic model with a vertical axis of symmetry. I mainly analyze the sensitivity kernels to understand the sensitivity of seismic data to anisotropy parameters. Then, I use a frequency domain scattering integral approach to invert for the optimal parameterization. The scattering integral approach is based on the explicit computation of the sensitivity kernels. I present a new method to compute the traveltime sensitivity kernels for wave equation tomography using the unwrapped phase. I show that the new kernels are a better alternative to conventional cross-correlation/Rytov kernels. I also derive and analyze the sensitivity kernels for a transversely isotropic model with a vertical axis of symmetry. The kernels structure, for various opening/scattering angles, highlights the trade-off regions between the parameters. For a surface recorded data, I show that the normal move-out velocity vn, ƞ and δ parameterization is suitable for a simultaneous inversion of diving waves and reflections. Moreover, when seismic data is inverted hierarchically, the horizontal velocity vh, ƞ and ϵ is the parameterization with the least trade-off. In the frequency domain, the hierarchical inversion approach is naturally implemented using frequency continuation, which makes vh, ƞ and ϵ parameterization attractive. I formulate the multi-parameter inversion using the scattering integral method. Application to various synthetic and real data examples show accurate inversion results. I show that a good background ƞ model is required to accurately recover vh. For 3-D problems, I promote a hybrid approach, where efficient ray tracing is used to compute the sensitivity kernels. The proposed method highly reduces the computational cost.
dc.language.isoen
dc.subjectFull Waveform Inversion
dc.subjectAnisotropy
dc.subjectMulti-parameter
dc.subjectSeismic Inversion
dc.subjectModeling
dc.subjectVTI
dc.titleMulti-parameter Analysis and Inversion for Anisotropic Media Using the Scattering Integral Method
dc.typeDissertation
dc.contributor.departmentPhysical Science and Engineering (PSE) Division
dc.rights.embargodate2018-10-25
thesis.degree.grantorKing Abdullah University of Science and Technology
dc.contributor.committeememberHoteit, Ibrahim
dc.contributor.committeememberLaleg-Kirati, Taous-Meriem
dc.contributor.committeememberStovas, Alexey
thesis.degree.disciplineEarth Science and Engineering
thesis.degree.nameDoctor of Philosophy
dc.rights.accessrightsAt the time of archiving, the student author of this dissertation opted to temporarily restrict access to it. The full text of this dissertation became available to the public after the expiration of the embargo on 2018-10-25.
refterms.dateFOA2018-10-25T00:00:00Z


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