Quantitative seismic interpretation of the Gassum Formation at the Stenlille aquifer gas storage

A quantitative seismic interpretation of the Gassum Formation at the onshore aquifer gas storage near the Danish town Stenlille is presented with its implications for exploiting the gas storage facility as a potential CO2 demonstration site. An available dataset including a 3D seismic volume and 20 wells was used to interrogate the following questions: (1) Is the seismic response of the natural gas stored in the Stenlille aquifer similar to a modelled CO2 fluid at equivalent burial depths?; (2) Can we map the injected natural gas distributions stored within the various reservoir zones and compartments in the Stenlille aquifer?; and (3) Can we better resolve the spatial reservoir heterogeneities and zone boundaries in the Gassum Formation? Our approach involves employing a set of quantitative interpretation tools based on the available 3D seismic post-stack volume and well logs. The quantitative interpretation results yield additional reservoir insights useful for building a robust static model for subsequent CO2 storage and de-risking. The present study is a part of recent projects (ConsenCUS and CCS2022−2024) carried out at GEUS.