Velocity model building and seismic imaging of the Gassum structure for potential CO2 storage in Denmark

CCS is an efficient and an inevitable way to tackle climate crisis. Denmark aims at carbon neutrality by exploring and utilizing potential storage sites for CO² sequestration. A series of upscaled high-resolution reflection seismic surveys have been planned and are currently being carried out across the country to investigate potential reservoir sites; the largest one being around the town of Gassum and targeting the reservoir sandstones of the Gassum Formation. A dual element recording system has been adapted and spaced MEMs-based recorder on a moving landstreamer system. Here, we present the longest profile of the Gassum survey, P9, from the nodal array. Given the long offset range of the nodal arrays and high-quality data acquired, we aim at employing various velocity model building approaches to characterize the Gassum structure and its four-way closure or domed-shaped structure. Preliminary processing work reveals the domed Gassum structure with quality. Future works in the velocity model employing traveltime tomography and full-waveform inversion would help to further improve the quality of the sections and better characterize the target reservoir.