How to Characterize a Potential Site for CO2 Storage with Sparse Data Coverage – a Danish Onshore Site Case

The paper demonstrates how a potential site for CO 2 storage can be evaluated up to a sufficient level of characterization for compiling a storage permit application, even if the site is only sparsely explored. The focus of the paper is on a risk driven characterization procedure. In the initial state of a site characterization process with sparse data coverage, the regional geological and stratigraphic understanding of the area of interest can help strengthen a first model construction for predictive modeling. Static and dynamic modeling in combination with a comprehensive risk assessment can guide the different elements needed to be evaluated for fulfilling a permit application. Several essential parameters must be evaluated; the storage capacity for the site must be acceptable for the project life of the operation, the trap configuration must be efficient to secure long term containment, the injectivity must be sufficient to secure a longstanding stable operation and finally a satisfactory and operational measuring strategy must be designed. The characterization procedure is demonstrated for a deep onshore aquifer in the northern part of Denmark, the Vedsted site. The site is an anticlinal structural closure in an Upper Triassic – Lower Jurassic sandstone formation at 1 800-1 900 m depth.