Quantification of fault-related leakage risk

The FRISK project focus on the risk related to faults in reservoirs under consideration for CO2 storage. In 2021 all partners have had good progress on developing new knowledge about faults and implement the knowledge into fault modelling tools relevant for addressing fault properties and risk assessment. Two papers have been published on the quantification of uncertainties in seismic interpretation of faults and how this can influence on further modelling and risk assessment. New experimental data on fault permeability for carbonate rich faults has been conducted in collaboration with University of Leeds and the interpretation and application of new data will be followed up in 2022. To better understand the range of permeability for typical seal and overburden formation in the North Sea, the NGI database has been reviewed and this data provided a very useful input for an attempt to model leakage rates along a fault zone in the Horda Platform area. The new modelling tool has the capacity to utilize various methods for assessment of fault thickness and permeability suitable for uncertainty quantification. The work has been presented as a TCCS conference paper and an open NCCS webinar. Integration of the fault flow model into reservoir simulations has started. A study describing fault zone permeability reduction due to deformation bands within the faulted reservoir has been presented as a TCCS conference paper. Method for handling non-linear problems in reservoir simulations are under development and further work on integration of overburden fault zone with the reservoir simulations has started. The FRISK project has had several meetings with the industry partners in the project discussion the modelling progress and industrial relevance of the new tool. International collaboration has been limited due to the covid 19 travel restrictions, but we are hoping to pick up on this in 2022.

Prediction of fault seal integrity has been identified as a major technology gap and obstacle for qualification of CO2 storage within faulted reservoirs with structural traps. Existing workflows and methods have limitations when it comes to including along-fault flow and dynamic changes related to increasing reservoir pressure during injection. The FRISK proposal has the ambitions to improve the fundamental understanding of fluid flow in faults and contribute to a better framework for fault derisking with application for CO2 site qualification. The proposed research activities is focused towards the Smeahia case study and includes: (1) mapping and quantification of fault complexity as a base for 3D risking of faults, (2) constrain static and dynamic fault flow properties from experimental data and field observations, (3) develop effective along-fault flow models and (4) quantify uncertainty in key controlling parameters and leakage rates. The main findings will be integrated and synthesised to quantify the fault related leakage-risk and outline how the new findings may contribute to the structural derisking for Smeaheia. Reduced uncertainty in fault related leakage risk may enable qualification of potential geological CO2 storage sites in the North Sea. Hence, the FRISK project answers directly to the priority area of the CLIMIT call on Large-scale storage of CO2 on the Norwegian shelf in the North Sea.

Publications from Cristin

Impact of deformation bands on fault-related fluid flow in field-scale simulations

Effective permeability of deformation bands in fault damage zones – Can deformation bands reduce the risk of fault leakage?

Adaptive stratified sampling for non-smooth problems

Upscaled Geocellular Flow Model of Potential Across-and along-Fault Leakage Using Shale Gouge Ratio

Along-strike permeability variation in carbonate-hosted fault zones

How Fault Interpretation Method may Influence the Assessment of a Fault-Bound C02 Storage Site

Effect of Mineral Processes and Deformation on the Petrophysical Properties of Soft Rocks during Active Faulting

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Hvordan sikrer vi trygg lagring av CO2 under havbunnen?

CCS: A Hidden Gem for Mitigating Climate Change

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How Fault Interpretation Method May Influence the Assessment of a Fault-bound CO2 Storage Site

Strategies to De-Risk Faults in the Subsurface for CO2 Storage: A Case Study from Smeaheia

Neogene Faulting and Evidence of Fluid Flow in the Caswell Sub-Basin (Browse Basin): Implications for CO2 Sequestration

Containment Risk Assessment and Management of CO2 Storage on the Horda Platform

Hvordan sikrer vi trygg fangst og lagring av CO2? : Hvor mye CO2 kan vi lagre på norsk sokkel, og hvordan gjør vi det?

Fault leakage analysis addressing vertical migration rates along faults

Overburden Fluid Migration along the Vette Fault Zone, North Sea, Using Different Fault Permeability Models

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Practical field-scale simulation approaches for quantification of fault-related leakage under uncertainty

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Adaptive Stratification Library on PyPI

Valuable new knowledge and models of storage risk related to faults in reservoirs

Underground storage of CO2 is taking off

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