Shallow Drilling in the NSB: characterising CO2 Storage Systems via Detailed Mapping and Imaging of Glacial Stratigraphy

• Main Authors: Furre, Anne-Kari, Stewart, Heather, Stewart, Margaret, Aagaard, Per
• Format: Text
• Language: English
• Published: EAGE Conference 2015
• Subjects: Earth Sciences; Glaciology; Marine Sciences; Sleipner; Ice Sheet
• Online Access: http://nora.nerc.ac.uk/id/eprint/512689/; https://nora.nerc.ac.uk/id/eprint/512689/1/SES15%20Glacistore%20Furre%20Stewart%20Stewart%20Aagard.pdf; http://www.eage.org/event/index.php?eventid=1259&evp=14329&ActiveMenu=&Opendivs=&act=det&prev=&ses=3281

The North Sea Basin (NSB) has been suggested as a potential site for CO2 storage (Element Energy 2010; EU 2009; 2011), due to its favourable geological setting, its proximity to sources, and pioneering operational experience storing CO2 at the Sleipner injection site (Halland et al., 2011, Arts et al. 2008). The shallow Neogene and Quaternary sediments of the NSB form the overburden and seal to these underlying CO2 reservoirs but are under-researched, even though the NSB is a mature petroleum system, penetrated by hundreds of wells. The up-to 1000 metre-thick Quaternary sediments are in general bypassed to reach the profitable hydrocarbon resources located deeper in the succession. Over the last 2.6 Ma the NSB has been subject to repeated cycles of glaciation and deglaciation (Gibbard et al. 2010). These Quaternary sediments have typically experienced rapid ice loading and unloading affecting the mechanical properties of the strata, fluid conductivity, and the effects of glacial erosion and deposition (e.g. incision by sub-glacial tunnel valleys). It is necessary to understand sedimentary architecture, compaction, cementation, and the role of connate fluids and microbial processes for CO2 site characterisation. This increases confidence in secure containment of injected fluids. The GlaciStore consortium was formed with the purpose of submitting a proposal to the International Ocean Discovery Program (IODP), for a drilling campaign addressing the following questions: • Explore Earth's climate history over the last 2.6 Ma in an area where the most complete sequence is preserved. • Better understand the geometry, dynamics, processes and wider impact of ice sheet development in the NSB. • Understand fluid flow and its evolution (dissolved gases, salts and isotopes) during a period of fluctuating pressure conditions in shale-dominated basins and its implications for CO2 storage. • Understand the impact on the geomechanical properties of containment barriers (<1000 metres below sea floor (mbsf)) caused by cycles of ...