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Bachelor Thesis

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This bachelor thesis is about seismic trace interpolation, data regularization and extrapolation using partial CRS stacks. I edit the underlying synthetic data record to create sparse data and prepare for extrapolation. The gaps appear randomly in mid-offset and specifically in near-offset. Subsequently, I compare the results of the interpolation with the traces I deleted from the record, examine data regularization and analyze the extrapolation. The interpolation process preserves arrival times and frequencies very well. Especially the arrival times in near-offset are within minimum tolerance. However some trace contain lowintensity noise over the entire frequency bandwidth. The results show an interpolation error for the direct wave. This error occurs because the linear move-out of the direct wave cannot be approximated by the hyperbolic approach of the partial CRS stack. Data regularization is interpolation for equally spaced intervals. These intervals can be defined precisely and therefore hold the accuracy of the interpolation process. Extrapolation issues a challenge to the partial CRS algorithm. The Fresnel zone defines physical boundaries for the partial CRS apertures. I calculated the extrapolation for more than double of these limitations. Thus, I expect extrapolation artifacts such as amplitude escalation and signal splitting. These expectations are answered by amplitude escalation, smearing and signal splitting, appearing at 1.5 times the Fresnel zone. Nevertheless, extrapolation supplies a reliable extension of the reflection events. For the sake of extrapolation artifacts limitations by the Fresnel zone ought not be breached. In conclusion, I validate seismic trace interpolation and data regularization processes of the partial CRS stack and I point out boundaries of the extrapolation process

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