Reducing Uncertainty in predicting the geological storage of CO2 - improved geomechanical models and calibration using seismic data

Although the scientific community and many governments agree that greenhouse gases resulting from the use of hydrocarbon fuels are primarily responsible for producing damaging global climate change, society is still heavily dependent on hydrocarbon fuels for everything from electricity generation, transport, and manufacturing.

Time scales involved for viable transitions to low carbon societies will likely be on the order of several decades and thus requiring immediate solutions for reducing current anthropogenic CO2 emissions into the atmosphere. Geological storage forms an integral component of the carbon capture, transport and storage (so-called CCS) engineering technology chain and is now recognized by most governments and scientists as a practical strategy with relatively immediate consequences in reducing global greenhouse gas emissions, continuing to meet the world's energy needs, and transitioning to low carbon economies.

When CO2 is injected and stored in a geological formation, the in situ stress field is altered immediately due to increased pore pressure and reduced temperature within the reservoir. This leads to deformation in both the reservoir and surrounding rock. This deformation can change the injection and storage characteristics of the geological formation. Furthermore, substantial changes can significantly compromise cap-rock integrity (i.e. the barrier to upward flow of buoyant CO2) through the formation fractures and/or the reactivation of existing fractures or faults.

The objective of this fellowship funding is to address the fundamental uncertainty related to reservoir stress as a response to the geological storage of CO2. The fellowship aims to make a step change in quantifying the uncertainty and risks due to the injection and storage of CO2 in geological storage sites.

To accomplish this, the research will develop and advance current approaches in building complex hydro-mechanical models using seismic data, and develop methods to calibrate state-of-the-art hydro-mechanical modelling tools using seismic and surface deformation data.

The main outcomes of the fellowship are to significantly improve our ability to: (i) assess the safety of geological storage sites in the early stages of development to reduce uncertainty and risk, and (ii) use integrated model predictions to provide a forecasting and mitigating tool to describe the behaviour of geological storage sites due to the injection and storage of CO2.

Impact

The fellowship provides an opportunity to advance the UK's current strengths and capabilities in CO2 storage modelling, prediction and risk quantification by addressing key limitations in integrated modelling workflows and providing valuable insight into the risks and challenges face in future storage activities.

The fellowship will have broad impact on a range of stakeholders interested in Carbon Capture and Storage (CCS), such as scientists, policy makers, regulators and the general public. The fellowship fits broadly into the field of multi-phase flow in porous, deformable media and hence is multidisciplinary.

The results can be translated to other key strategic energy areas, such as shale-gas exploitation and geothermal energy, but also by nature benefit scientists working on seismic, geodetic, fluid-flow and geomechanical methods in many basic and applied fields of research studying the impact of pressure and temperature changes on physical systems (e.g. volcanologic or ground-water research).

The impact of the proposed research will touch on: i. Economy: provide an opportunity to advance the UK's current strengths and capabilities in CCS, specifically targeting CO2 storage modelling, prediction and risk quantification; provide valuable data to assess the economic risks and challenges in large-scale storage activities; allow translation to other key strategic areas, such as geothermal energy and shale-gas exploitation. ii. Society: provide valuable data to inform policy and regulation for large-scale CCS geological storage activities as well as other key energy strategic areas, such as geothermal energy and shale-gas exploitation.

Grant

EP/K021869/1