Blar i UiS Brage på forfatter "Ahmed, Nisar"
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Adjoint-state method for seismic AVO inversion and time-lapse monitoring
Ahmed, Nisar (PhD thesis UiS;, Doctoral thesis, 2023)This dissertation presents seismic amplitude versus offset (AVO) inversion methods to estimate water saturation and effective pressure quantitatively in elastic and viscoelastic media. Quantitative knowledge of the saturation ... -
Constrained non-linear AVO inversion based on the adjoint-state optimization
Ahmed, Nisar; Weibull, Wiktor Waldemar (Peer reviewed; Journal article, 2022)Pre-stack AVO inversion of seismic data is a modeling tool for estimating subsurface elastic properties. Our focus is on the model-based inversion method where then unknown variables are estimated by minimizing the misfit ... -
Frequency-dependent AVO inversion applied to physically based models for seismic attenuation
Ahmed, Nisar; Weibull, Wiktor Waldemar; Quintal, Beatriz; Grana, Dario; Bhakta, Tuhin (Peer reviewed; Journal article, 2022)Seismic inversion of amplitude versus offset (AVO) data in viscoelastic media can potentially provide high-resolution subsurface models of seismic velocities and attenuation from offset/angle seismic gathers. P- and S-wave ...