Reducing uncertainty in predicting the risk of 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 my fellowship 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 or 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.

The fellowship will be conducted at the University of Leeds. The research environment at Leeds will allow me to continue to develop my CCS research, while working with some of the key people in this field. Prof Quentin Fisher has been the driving force behind integrated hydro-mechanics and petro-physics; Prof Bruce Yardley is at the forefront in researching geochemical effects of CO2 injection and fluid-rock; Prof Peter Taylor was former Division Head of the Technology Policy Division in CCS at the International Energy Agency; Prof Andrew Gouldson has proven experience in the policy and risk analysis of low carbon technologies; and Prof Andrew Shepherd has strong expertise in developing novel applications of InSAR to monitor surface deformation in complex terrains.