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The majority of the individual structures with potential for CO 2 storage are related tomovement of the Zechstein salt (figure 5). The salt movement has caused formation of awide range of structures from gentle domes to diapirs. The dome structures most oftenform anticlines with 4-way closures and lack of significant faulting. The diaperstructures on the contrary breaks through the overlaying deposits and faults accompanythe salt structures. It might be possible to find traps with storage potential related to thediapirs and side-sealed by the salt, but investigation and mapping is complicated bydisturbance of the seismic signals close to the salt structures. A few structures are relatedto faulting, for example the Vedsted Structure, these structures may have 2, 3 or 4 wayclosures (figure 5).Figure 5: Cross-section trending SW–NE across the Danish area from the Ringkøbing-Fyn High (SW) to the Skagerrak-Kattegat Platform (NE). Position of the cross-section isshown on figure 2. The section illustrates the variation of the salts structures rangingfrom gentle four-dip dome closures with a fully preserved overlying sedimentary columnto salt diapirs penetrating most of the Mesozoic succession. The Danish area has severallarge dome structures with preserved reservoirs and cap rocks.1) Soft dome structure, 2)Diapirs, 3) Fault related structure (The Vedsted structure). Modified from Vejbæk 1990,1997.In the GeoCapacity project a number of structures were selected and evaluated withregards to the possibility for CO 2 storage (figure 4). The selected structures are mainlyidentified on the basis of old seismic data, and in case of future utilization, the structureswill need further investigations and qualification based on new seismic data and wells.The data suggest that the structural traps alone may provide storage for at least 16Gt CO 2assuming that the effective storage capacity is 40% of the total pore volume within thestructure. Unfaulted, thick units of claystones or evaporites seal the traps (Larsen et al.2003).Apart from the ten structures described in the GeoCapacity project many othergeological structures within the Danish territory may prove suitable for CO 2 storage(figure 4). Especially in the eastern part of the Norwegian-Danish Basin and close to theSorgenfrei-Tornquist Zone where the sedimentary succession is extensive, the potentialfor CO 2 storage seems to be promising.The potential for CO 2 storage is limited at the Skagerrak-Kattegat platform area becauseof a thin sedimentary cover. However close to the Sorgenfrei-Tornquist Zone the6Risø International Energy Conference 2011 Proceedings Page 53