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The seismic reflection method for imaging of the earth's interior is an essential part of the exploration and exploitation of hydrocarbon resources. A seismic survey should be designed such that the acquired data leads to a sufficiently accurate subsurface image. The survey geometry analysis method presented in this thesis is based on the previously developed focal beam analysis concept. It emphasizes the separate analysis of the source geometry and the detector geometry. In this thesis the concept is implemented for application to an inhomogeneous subsurface, by using recursive depth extrapolation of wavefields. In addition, a direct link is made to reservoir characterization. The analysis shows whether proper focusing of the wavefield can be achieved for the chosen source and detector geometries, how the image resolution is affected, and how the angle-dependent amplitudes are affected. This includes the influences of the acquisition geometry, the overburden structure, and the focusing operators. Both P-wave acquisition and converted wave acquisition can be handled. Analysis of well-sampled, stationary geometries shows the fundamental limitations of the acquisition system. Analysis results for - more realistic - parallel and orthogonal geometries show which information is lost in practice. For subsalt imaging, a strong dependence of image quality on the target point location is observed, in addition to fundamental limitations to the image quality due to critical reflection at the salt boundaries. |
