Glacistore: Understanding Late Cenozoic Glaciation and Basin Processes for the Development of Secure Large Scale Offshore CO2 Storage (North Sea).
Abstract:The sedimentary strata of the North Sea Basin (NSB) record the glacial and interglacial history of environmental change in the Northern Hemisphere, and are a proposed location for the engineered storage of carbon dioxide (CO2) captured from power plant and industrial sources to reduce greenhouse gas emissions. These aspects interact in the geomechanical and fluid flow domain, as ice sheet dynamics change the properties of potential seal and reservoir rocks that are the prospective geological storage strata for much of Europe’s captured CO2.
The intensification of the global glacial-interglacial cycle at the onset of the Pleistocene (2.5-2.7 Ma) was a critical tipping-point in Earth’s recent climate history. The increased severity of glaciations at the Plio-Pleistocene boundary triggered the first development of large-scale continental ice sheets in the Northern Hemisphere. The central part of the NSB preserves a unique history of the depositional record spanning at least the last 3 Ma, which also forms the overburden and seal to the underlying CO2 reservoirs. There is good evidence that these ice sheets created strong feedback loops that subsequently affected the evolution of the Quaternary climate system through complex ocean-atmosphere-cryosphere linkages.
Understanding NSB dynamics, including the role of fluids in controlling compaction, cementation, and diagenetic processes in shale-dominated basins, is essential for CO2 storage site characterisation to increase understanding and confidence in secure storage. An increased understanding of the overlying sequence will inform quantitative predictions of the performance of prospective CO2 storage sites in glaciated areas in Europe and worldwide; to include improved resolution of glacial cycles (depositional and chronological framework), characterise pore fluids, flow properties of glacial landforms within the sequence (e.g. tunnel valleys) and the geomechanical effects (quantify compaction, rock stiffness, strength and stress profiles) of advancing and retreating ice on the underlying strata to verify and constrain models of glaciation.
This presentation describes current work and introduces a proposal submitted to the Integrated Ocean Discovery Program (852-Pre) by the authors.