Unmasking fault zones in CO2 storage – a true calibration
Genna Petho A * , Hadi Nourollah A and Michael Rieger AA
Genna Petho is a Reservoir Engineer with experience across multiple sectors in the oil and gas industry at major Australian operators, including operations of offshore Australian gas and oil fields, well planning and execution and dynamic reservoir modelling. She currently provides subsurface technical expertise for upcoming CCS projects across Australia, including storage site evaluation, simulation studies, risk assessments and monitoring and verification planning. She holds a BEng in Petroleum Engineering (with Honours) and a BSc in Geology and Geophysics. |
Dr Hadi Nourollah is a Senior Geophysicist with 20 years of international experience in Petroleum and CCS industries. Hadi received his Master’s degree in Petroleum Geosciences at Imperial College London, and completed his PhD in Geophysics at Curtin University. He has worked for National Oil Companies in the Middle East, operators in Southeast Asia and directed an international consultancy in Australia for a decade prior to joining the global CCUS leader CO2CRC. |
Michael Rieger is a Geomechanics Specialist at CO2CRC with experience in the petroleum industry, holding a Bachelor of Science (Honours) degree in Petroleum Geology and Geophysics. Prior to joining CO2CRC, Michael worked as a Geoscientist at Santos, focussed on delivering geomechanical support for fracture stimulation programs. At CO2CRC, Mike focusses on reservoir geomechanics for CCS projects. His work emphasises developing innovative modelling workflows that integrate strain and acoustic data. In addition, Mike is pursuing a Master’s of Geomechanical Engineering at the University of Arizona, to deepen his knowledge in this field. |
Abstract
The risk of fault leakage and understanding flow along and across fault planes is a core component of risk evaluation in geological carbon storage (GCS) projects. The Brumbys Fault, a shallow fault at the Otway International Test Centre, serves as a pivotal component in evaluating the implications of CO2 injection into faulted formations. A first-of-its-kind controlled CO2 injection experiment was conducted in April 2024 as part of the Otway Shallow Fault Project. Sixteen tonnes of CO2 was injected adjacent to the Brumbys Fault and closely monitored to observe the CO2 migration pathway. Although analysis of the collected data is still ongoing, the experiment has already provided valuable insights on CO2 migration in the presence of a fault zone. Focus is placed on providing a calibration point pivotal for quantifying the risk of fault leakage in future industrial-scale GCS projects. Initial findings from monitoring measurements and the history matching of injection data have already been leveraged to enhance understanding of potential risks in such environments. The study facilitates the comparison of forward models with real data measurements, empowering industry to make necessary adjustments in their risk evaluation processes. This research sheds light on the complexities of CO2 injection in faulted geological formations and underscores the critical role of precise risk assessment in ensuring the safety and effectiveness of such operations. The study’s findings provide significant contributions to the understanding of fault leakage risks and offers essential guidance for future GCS projects navigating similar challenges.
Keywords: Brumbys, CO2, faults, injection, leakage, migration, monitoring, Otway, risk, storage.
Genna Petho is a Reservoir Engineer with experience across multiple sectors in the oil and gas industry at major Australian operators, including operations of offshore Australian gas and oil fields, well planning and execution and dynamic reservoir modelling. She currently provides subsurface technical expertise for upcoming CCS projects across Australia, including storage site evaluation, simulation studies, risk assessments and monitoring and verification planning. She holds a BEng in Petroleum Engineering (with Honours) and a BSc in Geology and Geophysics. |
Dr Hadi Nourollah is a Senior Geophysicist with 20 years of international experience in Petroleum and CCS industries. Hadi received his Master’s degree in Petroleum Geosciences at Imperial College London, and completed his PhD in Geophysics at Curtin University. He has worked for National Oil Companies in the Middle East, operators in Southeast Asia and directed an international consultancy in Australia for a decade prior to joining the global CCUS leader CO2CRC. |
Michael Rieger is a Geomechanics Specialist at CO2CRC with experience in the petroleum industry, holding a Bachelor of Science (Honours) degree in Petroleum Geology and Geophysics. Prior to joining CO2CRC, Michael worked as a Geoscientist at Santos, focussed on delivering geomechanical support for fracture stimulation programs. At CO2CRC, Mike focusses on reservoir geomechanics for CCS projects. His work emphasises developing innovative modelling workflows that integrate strain and acoustic data. In addition, Mike is pursuing a Master’s of Geomechanical Engineering at the University of Arizona, to deepen his knowledge in this field. |
