Geomechanical Assessment of CO2 Storage Reservoir Integrity Post-closure (GASRIP)

Lead Research Organisation: National Oceanography Centre (WEF011019)
Department Name: Science and Technology

Abstract

Injecting carbon dioxide (CO2) into deep geological formations is recognized worldwide as the only realistic mitigation technology that can reduce current anthropogenic CO2 emissions to meet national targets by 2050. However, Carbon Capture and Storage (CCS) have aroused public concerns over potential surface leakage of CO2 from geological reservoirs, limiting the number of potential storage sites. European countries, including the UK, have considered depleted oil and gas fields and saline aquifers for CO2 storage (e.g. Sleipner field, North Sea), while a number of projects in the United States have focused on CO2 injection for enhanced oil recovery (EOR) in depleted or unconventional hydrocarbon reservoirs.
Geological reservoirs are complex systems. Their geomechanical integrity can be affected by CO2-fluid-rock interactions following injection of CO2, which can be quantified in terms of Thermal, Hydrological, Mechanical and Chemical coupled phenomena (THMCs). THMCs induced by CO2 injection can lead to detrimental enhanced seismicity and CO2 leakage to the surface. So, the advent of CCS and EOR-CCS operations has triggered the need for more research to preserve the geomechanical integrity of reservoirs during the whole CO2 storage cycle (lasting 100s years). To date, researchers have focused on the induced changes in the physical properties of the reservoir during CO2 injection (transition from brine-bearing to CO2-bearing formations) and associated overpressure effects. It is generally assumed that following the interruption of CO2 injection, the reservoir pressure decreases, the CO2 plume migrates and natural imbibition leads to aquifer recharge. However, CO2 injection is a drying process that triggers complex salt precipitation phenomena in brine saturated formations. Several studies have focused on the risks associated with porosity and permeability reduction with respect to injection efficiency and storage capacity. A less appreciated fact is that salt crystals growing under confinement have the potential to damage the rock by exerting enormous pressures (haloclasty). After ceasing the CO2 injection, the aquifer recharge leads to salt dissolution and reservoir compaction.
The hypothesized reversibility of salt precipitation in CO2 storage contexts has yet to be investigated. Which phenomena do we expect to affect reservoir integrity during the natural aquifer recharge post-CO2 injection? Can we control them? The energy industry is transforming as we move to a lower carbon world; CCS and EOR-CCS are becoming essential practices for the oil and gas industry, a vital sector for the UK economy. Addressing these questions is crucial for the safe CCS operation at the scales needed to mitigate greenhouse gas emissions for the UK, and at the same time improving recovery rates from hydrocarbon reservoirs (e.g., UK North Sea fields). This project seeks to address the UK Industrial Strategy's clean energy agenda by reducing CCS risks, and providing a possible new EOR method.
Geomechanical Assessment of CO2 Storage Reservoir Integrity Post-closure (GASRIP) is a project primarily designed to study how CO2-brine induced-salt precipitation/dissolution affects geomechanical integrity of CO2 storage reservoirs. By looking at changes in the elastic, mechanical and transport properties of natural sandstones in the laboratory, GASRIP will assess variations in the mechanical properties in saline siliciclastic reservoirs post-CO2 injection. By analysing carbonate-rich sandstones, GASRIP will determine the mechanical and chemical post-CO2 injection effects on chemically reactive reservoirs. This information is needed for the potential use of salt precipitation in a controlled manner to improve the transport properties and the viable production of oil and gas from tight reservoirs (EOR alternative). By integrating the results in a numerical model, GASRIP will offer a valuable tool for risk assessment of CO2 storage reservoirs post-closure.

Related Projects

Project Reference Relationship Related To Start End Award Value
NE/R013535/1 02/01/2018 31/10/2019 £327,975
NE/R013535/2 Transfer NE/R013535/1 01/11/2019 30/06/2021 £165,122
 
Description We have found geophysical evidences of CO2-induced salt precipitation during Geological CO2 Storage (GCS), from which we enable the quantification of the salt volume precipitated in the pore space, for the first time. This induced precipitation has been identified as an important risk factor during GCS activities in high saline aquifers, in terms of injectivity reduction and associated overpressure. But our results have also identified rock weathering induced by the salt precipitation that could compromise the geomechanical integrity of the reservoir. Therefore, this finding highlights the importance of an early detection of CO2-induced salt precipitation during GCS, and demonstrates the potential of the common geophysical tools used for reservoir monitoring (i.e., seismic and electromagnetic surveys) to identify and quantify the evolution of the phenomenon.
Exploitation Route The datasets generated in the rock physics laboratory at the National Oceanography Centre, Southampton, are the most valuable outcome this project will generate. Every dataset is being publicly stored in the National Geoscience Data Centre.
Sectors Energy,Environment

URL https://projects.noc.ac.uk/gasrip/
 
Title Brine-CO2 flow-through test in synthetic sandstone with oblique fractures 
Description Here we present the dataset collected during a brine-CO2 flow-through test using a synthetic sandstone with oblique fractures, performed under realistic reservoir conditions stress. We monitored geophysical, mechanical and transport properties, for drainage and imbibition conditions, representative of the injection and post-injection stages of the CO2 storage process. We collected ultrasonic P- and S-wave velocities and their respective attenuation factors, axial and radial strains, electrical resistivity, pore pressure, temperature and brine and CO2 partial flows (from which relative permeability was later calculated). 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? Yes  
Impact This dataset has been partially published in https://doi.org/10.1016/j.petrol.2019.106551 
URL https://www.bgs.ac.uk/services/ngdc/citedData/catalogue/abc38c58-3a69-42ed-86ac-1502509bd88c.html
 
Title CO2-induced salt precipitation test in sandstone 
Description Here we present the dataset collected during a CO2 flow-through test using a synthetic sandstone of high porosity and permeability, originally saturated with high salinity brine, performed under realistic shallow reservoir conditions stress. During the test, we collect geophysical data (elastic and electrical properties) which record petrophysical variations in the rock related to the precipitation of salt, induced by a continuous CO2 flow through the sample. 
Type Of Material Database/Collection of data 
Year Produced 2020 
Provided To Others? Yes  
Impact This dataset evidences detectable geophysical signatures (elastic waves and electrical resistivity) associated to CO2-induced salt precipitation in saline aquifers, for the first time. The results have been assessed in the paper Geophysical early warning of salt precipitation during geological carbon sequestration, Scientific Reports, 10(1), 16472, doi:10.1038/s41598-020-73091-3 
URL https://www.bgs.ac.uk/services/ngdc/citedData/catalogue/6c9d05aa-f1f2-49a9-868e-3d2d5947ad54.html
 
Description GASRIP - Gobierno de Canarias (GC) - University of La Laguna (ULL) 
Organisation University of La Laguna
Country Spain 
Sector Academic/University 
PI Contribution Fundamental research collaboration between GASRIP and the Canarian institutions GC and ULL to assess the potential of basalt rocks in CCS from an experimental approach using Canarian basalt samples.
Collaborator Contribution GC and ULL have provided with 25 rock samples of high porosity/permeability, particularly selected to study how transport, elastic and mechanical properties are affected by high pressure low temperature CO2 injection activities.
Impact No outputs yet. The first experiment was recently finished. Currently, the collected data are being processed.
Start Year 2018
 
Description GASRIP - ITN-SALTGIANT 
Organisation National Oceanography Centre
Country United Kingdom 
Sector Academic/University 
PI Contribution Fundamental research collaboration between GASRIP and ITN-SALTGIANT
Collaborator Contribution Experimental configuration and work supervision of the (ITN-SALTGIANT) PhD student Mike Dale. First results obtained late 2019 and interpretation/discussion is ongoing
Impact None
Start Year 2019
 
Description GASRIP - OASIS 
Organisation Colorado School of Mines
Country United States 
Sector Academic/University 
PI Contribution Fundamental research collaboration between GASRIP and the Department of Geosciences, University of Oslo (UiO), Curtin University (CU), Colorado School of Mines (CSM), Norwegian Computing Center (NR), Norwegian Geotechnical Institute (NGI), through the project OASIS (Overburden Analysis and Seal Integrity Study for CO2 Sequestration in the North Sea).
Collaborator Contribution Experimental work is being conducted to improve the understanding of the interactions between geophysical and mechanical behaviour of CO2 storage formation and cap rock.
Impact None
Start Year 2018
 
Description GASRIP - OASIS 
Organisation Curtin University
Country Australia 
Sector Academic/University 
PI Contribution Fundamental research collaboration between GASRIP and the Department of Geosciences, University of Oslo (UiO), Curtin University (CU), Colorado School of Mines (CSM), Norwegian Computing Center (NR), Norwegian Geotechnical Institute (NGI), through the project OASIS (Overburden Analysis and Seal Integrity Study for CO2 Sequestration in the North Sea).
Collaborator Contribution Experimental work is being conducted to improve the understanding of the interactions between geophysical and mechanical behaviour of CO2 storage formation and cap rock.
Impact None
Start Year 2018
 
Description GASRIP - OASIS 
Organisation Norwegian Geotechnical Institute
Country Norway 
Sector Private 
PI Contribution Fundamental research collaboration between GASRIP and the Department of Geosciences, University of Oslo (UiO), Curtin University (CU), Colorado School of Mines (CSM), Norwegian Computing Center (NR), Norwegian Geotechnical Institute (NGI), through the project OASIS (Overburden Analysis and Seal Integrity Study for CO2 Sequestration in the North Sea).
Collaborator Contribution Experimental work is being conducted to improve the understanding of the interactions between geophysical and mechanical behaviour of CO2 storage formation and cap rock.
Impact None
Start Year 2018
 
Description GASRIP - OASIS 
Organisation Norwegian Geotechnical Institute
Country Norway 
Sector Private 
PI Contribution Fundamental research collaboration between GASRIP and the Department of Geosciences, University of Oslo (UiO), Curtin University (CU), Colorado School of Mines (CSM), Norwegian Computing Center (NR), Norwegian Geotechnical Institute (NGI), through the project OASIS (Overburden Analysis and Seal Integrity Study for CO2 Sequestration in the North Sea).
Collaborator Contribution Experimental work is being conducted to improve the understanding of the interactions between geophysical and mechanical behaviour of CO2 storage formation and cap rock.
Impact None
Start Year 2018
 
Description GASRIP - OASIS 
Organisation University of Oslo
Country Norway 
Sector Academic/University 
PI Contribution Fundamental research collaboration between GASRIP and the Department of Geosciences, University of Oslo (UiO), Curtin University (CU), Colorado School of Mines (CSM), Norwegian Computing Center (NR), Norwegian Geotechnical Institute (NGI), through the project OASIS (Overburden Analysis and Seal Integrity Study for CO2 Sequestration in the North Sea).
Collaborator Contribution Experimental work is being conducted to improve the understanding of the interactions between geophysical and mechanical behaviour of CO2 storage formation and cap rock.
Impact None
Start Year 2018
 
Description GASRIP - OmanDP 
Organisation University of Southampton
Department Ocean and Earth Science
Country United Kingdom 
Sector Academic/University 
PI Contribution Fundamental research collaboration between GASRIP and OmanDP project to assess transport and elastic characterization of ophiolitic formations.
Collaborator Contribution Experimental configuration and supervise of the work developed by the (OmanDp) PhD student Alad Evans. Experiments conducted during the las quarter of 2019 and data will be processed early 2020.
Impact None
Start Year 2019
 
Description GASRIP - STEMM-CCS (H2020-LCE-2015-1) and CHIMNEY (NE/N016130/1). 
Organisation University of Southampton
Country United Kingdom 
Sector Academic/University 
PI Contribution GASRIP designs and conducts experiments in the rock physics laboratory at the National Oceanography Centre, Southampton (NOCS), which also satisfy goals for the two large CCS projects STEMM-CCS (H2020-LCE-2015-1) and CHIMNEY (NE/N016130/1)
Collaborator Contribution STEMM-CCS (H2020-LCE-2015-1) and CHIMNEY (NE/N016130/1) contribute to the improvement of the lab facilities, which in turn lead to improve the quality of the experimental data acquire during GASRIP experiments.
Impact Falcon-Suarez, I.H., Amalokwu, K., Delgado-Martin, J., Callow, B., Robert, K., North, L., Sahoo, S.K. & Best, A.I., 2018. Comparison of stress-dependent geophysical, hydraulic and mechanical properties of synthetic and natural sandstones for reservoir characterization and monitoring studies, Geophysical Prospecting (https://doi.org/10.1111/1365-2478.12699).
Start Year 2018
 
Description GASRIP - University of A Coruna (UDC). 
Organisation University of A Coruña
Country Spain 
Sector Academic/University 
PI Contribution Fundamental research collaboration between GASRIP and UDC, to study salt precipitation effects on clean sandstones (Corvio sandstone) associated with CO2 injection in saline aquifer reservoirs.
Collaborator Contribution UDC provided with Corvio sandstone samples, the rock selected for running some CO2-fluid-rock interaction experiments at the NOC. As part of this collaboration, the PhD student Andrea Muñoz-Ibáñez (UDC) has developed her research from March to June 2018 at the NOC, within the frame of GASRIP.
Impact Falcon-Suarez, I.H., Amalokwu, K., Delgado-Martin, J., Callow, B., Robert, K., North, L., Sahoo, S.K. & Best, A.I., 2018. Comparison of stress-dependent geophysical, hydraulic and mechanical properties of synthetic and natural sandstones for reservoir characterization and monitoring studies, Geophysical Prospecting, (https://doi.org/10.1111/1365-2478.12699).
Start Year 2018