Stress history and reservoir pressure for improved quantification of CO₂ storage containment risks (SHARP Storage)

Carbon Capture and Storage (CCS) is now maturing in Europe and worldwide with several Net Zero projects emerging. Hence, the need for safe and reliable CO₂ storage sites is accelerating and the reliable assessment of large-scale storage options at the gigatonne-per-year scale is critical.

The SHARP project addresses three Priority Research Directions identified in the Mission Innovation Report required to improve current technologies to deliver CO₂ storage volumes at the scale needed to meet demands for large scale storage. The geomechanical response to CO₂ injection is one of the key uncertainties in assessing proposed storage sites. The SHARP project aims to reduce this uncertainty with the ambitious goal of improving the accuracy of subsurface CO₂ storage containment risk management to a level acceptable to both commercial and regulatory interests. The project will be delivered through a multidisciplinary, transnational consortium of 16 partners from 5 countries. The development and integration of models for subsurface stress, rock mechanical failure and seismicity will mature the technology for quantification of subsurface deformation, thereby leading to cost-efficient CO₂ subsurface risk monitoring and management.

Key activities for the project include to: develop basin-scale geomechanical models that incorporate tectonic and deglaciation effects, and use newly developed constitutive models of rock/sediment deformation (WP1); improve knowledge of the present-day stress field in the North Sea from integrated earthquake catalogues and a comprehensive database of earthquake focal mechanisms (WP2); quantify rock strain and identify failure attributes suitable for monitoring and risk assessment using experimental data (WP3); develop more intelligent methods for in situ monitoring of rock strain and failure, and fluid pressure and movement (WP4); quantify containment risk using geomechanical models and observations from the field and laboratory (WP5); communicate technology development on containment risk to industry and regulators (WP6).

The SHARP project is expected to accelerate the maturation of six case studies from sites in the North Sea and India. SHARP will help to scale up the following saline aquifer prospects: the Northern Lights CO₂ storage project in the Horda area (N); emerging storage prospects in the Greater Bunter Sandstone area, which encompass the Endurance site (UK); the Hanstholm structure (DK). These North Sea projects will benefit from transferring knowledge from pioneering and more mature work in the Horda area. Furthermore, application to well-characterised offshore depleted oil and gas fields, like Nini (DK) and Aramis (NL), will accelerate their transformation into viable and safe CO₂ storage sites. India has high focus on emission reduction using CCUS and an onshore case study for CO₂ EOR will be matured using learning elements from across Europe to kick-start CO₂ injection and storage projects in India. Integrated involvement from international CO₂ storage operators in the consortium will ensure that the SHARP project will have a high impact on CCS development in Europe and globally. New technology for quantification of subsurface deformation and cost-efficient CO₂ subsurface risk management will provide effective tools for containment risk assessment. Strategies for monitoring deformation and induced seismicity will be communicated to storage site operators and regulators to increase confidence in storage safety and assessing seismicity risks. The SHARP integrated seismic catalogue and rock properties database will facilitate access to critical data for containment risk analysis, supporting upscaling of existing project as well as maturing new areas. This work is in line with the EU SET plan activity of unlocking European storage capacity, and the CLIMIT priority on Large-scale storage of CO₂ on the Norwegian shelf in the North Sea, as well as other national priority areas.