Innovative High-Density Seismic Data Acquisition and Processing Strategies for Reliable Characterization of Radioactive Waste Geological Repositories

Summary Reliable characterization of deep geological repositories (DGR) for radioactive waste requires seismic imaging of exceptionally high resolution due to complex geology, strict safety requirements and societal sensitivity. This paper presents an integrated approach combining optimized spatial sampling, dedicated survey design and advanced seismic data processing technologies, based on experience from the ASSE 3D seismic project conducted in a complex salt environment. The results demonstrate that increased acquisition density is extremely important for improved imaging quality and frequently must be supported by advanced processing-driven workflows. Advanced processing technologies, including non-invasive noise attenuation, structure-oriented interpolation, advanced prestack time and depth migration in anisotropic media and diffraction imaging, significantly enhance the imaging of steep structures, fault zones and potential migration pathways. The presented methodologies reduce geological uncertainty and form a transferable framework for seismic investigations supporting the assessment and long-term safety evaluation of deep geological repositories.