Seismic Investigations for the Final Disposal of Spent Nuclear Fuel in Finland

The paper reviews the seismic data processing techniques based on a version of the Radon transform, developed for characterizing non-planar and spatially limited structures of arbitrary orientations in crystalline rock. The examples are taken from the VSP surveys carried out in the borehole KR6, at the Olkiluoto site in SW Finland. Polarization analysis applied in the transform space allows the positions of the reflectors to be determined by estimating the direction of the arrival of the reflected waves. The approach permits the determination of both the 3D-position and local orientation of the observed reflectors. Anisotropic effects are included and accounted for in the analysis.