2D Reflection Seismic Imaging of Rødby Structures, Denmark: Geological Conditions for CO2 Sequestration

Abstract: Amidst the global climate action movement, geologic carbon storage (GCS) has emerged as a pivotal strategy for mitigating atmospheric CO2 levels, offering environmental and economic opportunities. This thesis targets the Bunter Sandstone Formation within the Rødby structures in Denmark, focusing on seismic Profile 1. Profile 1 is chosen as it crosses over the existing domal structure, and this will enable to investigate the closure or the extension of the domal structure, and also to evaluate its capacity for CO2 sequestration. Utilizing 2D Reflection Seismic Imaging and collaborating with the Geological Survey of Denmark and Greenland (GEUS), the study employs advanced seismic techniques to analyse the Triassic period sandstone formation.  The seismic data for Profile 1 was acquired during June-July 2023 as part of GEUS's national GCS projects by Uppsala University’s Geophysics Program, utilizing the SeisMoveTM dual-element recording system. A total of 991 shots were recorded by 1030 wireless recorders in a fixed geometry, enhancing the signal-to-noise ratio through vertical stacking of repeated shot records. The data acquisition parameters were carefully selected based on similar projects involving pilot and upscaling work conducted in Denmark prior to the Rødby survey. These parameters were influenced by experiences gained during previous successful applications in Denmark and similar environments, ensuring the retrieval of high-resolution seismic reflection images across a wide depth range. The results reveal the presence of a potential new domal structure within the Rødby region, which could substantially influence the area's capacity for carbon storage. The new possible domal structure extend toward east of the survey area and this discovery suggests the need for further investigations to comprehensively assess the extent of this new structure. Therefore, this study enhances the understanding of the Rødby region's subsurface geology; and by advancing the application of carbon capture and storage technologies, this study aligns with Denmark's climate initiatives and contributes to global climate change mitigation efforts.