Innanen, Kristopher A.Izadi, Hormoz2020-09-042020-09-042020-09-02Izadi, H. (2020). Application of 1-D Inverse Scattering to Inversion of Laboratory Seismic Data and Distributed Acoustic Sensing Data (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/112493The Born series provides a framework for constructing a connection between Earth model parameters and a wavefield characterised by perturbation about a known reference wavefield. The inverse scattering series provides a linear and a nonlinear expression for approximating Earth’s model parameters. Based on our results, the linear expression provides an accurate approximation of the 1-D depth varying velocity profile. However, with increasing contrast, one has to utilise the nonlinear expression for increased accuracy. In seismic inversion, a major problem relates to the bandlimited nature of recorded seismic data, limiting the inversion for absolute amplitudes. Numerical results on a 1-D synthetic model demonstrate the capacity of the algorithm to recover low frequency information, critical for accurate inversion. By extending the application of projection onto convex sets (POCS) to 1-D physical modelling data, we obtain an accurate reconstruction of the dataset. Inversion of the data demonstrates the advantage of nonlinear inverse scattering in approximating a relatively accurate velocity profile. In comparison, the linear scattering expression fails to provide a reasonable estimate of reflectors beyond the first interface. One of the areas of growing interest in the field of exploration geophysics is the application of optical fibre sensing technology. Recent studies suggest the advantage of this technique in providing a greater range of applicability in comparison to traditional methods. Among various Optical time-domain reflectometer (OTDR) arrangements, the intensity based measurement is generally limited by the nonlinear response of a signal to external disturbances such as strain. This has served as a motivation in the second half of this thesis to frame the problem as a 1-D scattering problem, in an attempt to apply the Born series to recover information related to variations in external measurements such as strain. Our attempts to utilise the Born series fails to provide an accurate estimation of changes in location of scattering points. This is primarily due to the complexity of the model and interference of backscattered optical pulse within the fibre. Continued research could potentially provide a framework for a robust detection of external perturbation based on variation in intensity.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.Born seriesInverse scatteringFrequency interpolationNonlinear inversionProjection onto convex sets (POCS)Optical time-domain reflectometer (OTDR)Intensity based OTDRBorn approximationSeismic reflection and transmission methodsDistributed acoustic sensing (DAS)Geophysicsdoctoral thesis10.11575/PRISM/38165