In the context of addressing climate change and achieving carbon neutrality, carbon dioxide capture and storage (CCS) technology is widely used to reduce greenhouse gas emissions. However, the surface uplift caused by CO2 injection still lacks systematic theoretical understanding and quantitative prediction methods, especially in the early stages of the project, which is limited by complex geological conditions and insufficient data. As an analytical solution method, the Geertsma model provides a possibility for the preliminary evaluation of CCS surface deformation with its high efficiency and simplicity.
Based on the Geertsma analytical model, this study established a multi-site surface uplift prediction framework, selected five representative CCS projects, In Salah, Sleipner, Weyburn, Gundih and Saskatchewan, as research objects, collected their field geological parameters, applied full factorial design to evaluate the sensitivity of the model input parameters to the prediction results, and compared and verified them with the CMG-GEM numerical simulation results. The results show that the Geertsma model can reasonably reflect the impact of pressure changes on surface deformation under the assumption of a uniform elastic medium and a disc-shaped reservoir. Sensitivity analysis further revealed that reservoir thickness, pressure change, and reservoir depth are the key factors affecting the amplitude of surface uplift. While the influence of Poisson’s ratio is relatively small.
Through multi-site analysis and model comparison, this study verified the applicability and limitations of the Geertsma model in early site selection assessment and parameter sensitivity analysis of CCS. It provided a theoretical basis and technical reference for improving the safety and prediction ability of CO2 geological storage projects.

CO2 emissions are a major driver of global warming, contributing significantly to the level of climate change. One promising solution to mitigate this issue is Carbon Capture and Storage, which involves capturing CO2 emissions from industrial sources and securely storing them in reservoirs or aquifers. The study investigates the impact of large-scale reservoir heterogeneity on the efficiency of the CO2 storage by using reservoir models inspired by the Sobrarbe Deltaic Complex outcrop in Ainsa, Spain. Utilizing Google Earth, RRM (Rapid Reservoir Modeling), and CMG software, different reservoir realizations were created, incorporating various levels of petrophysical properties and impermeable layers within the reservoir. The models simulated 100 years of CO2 injection and monitoring. Results indicate that the Base Model, characterized by continuous impermeable layers and high porosity and permeability values, represented the highest cumulative trapped CO2, capturing approximately 3 billion kg of CO2. Models with patchy impermeable layers and lower petrophysical properties values represented lower CO2 trapping efficiency. The results highlight the critical role of reservoir heterogeneity in determining the storage potential and pressure stability of CO2 storage projects, offering valuable insight into the feasibility of carbon storage initiatives.

The storage of carbon dioxide is now regarded as a critical industrial application aimed at mitigating its accumulation in the atmosphere. Reservoirs and aquifers have been identified as viable alternative locations. This report seeks to examine the impact of sedimentological heterogeneity on the development and migration of CO2 plumes over time. The study uses the Roda Sandstone Formation as a case study, primarily due to the presence of carbonate-cemented layers within the Gilbert-delta lobes, which contribute to reservoir heterogeneity commonly observed in subsurface formations. The utilization of a sketch-based modeling approach was employed in constructing the geo-models represented by Rapid Reservoir Modeling (RRM) software since the Roda Sandstone is an exposed section in Isabena Valley in Spain. Furthermore, various realizations are constructed using different parameters of the cemented layers to comprehensively comprehend all potential scenarios. The aforementioned observations pertain to variations in the thickness and lateral continuity of the cemented layers. Additionally, dynamic modeling is also performed by injecting CO2 into the reservoir for 50 years. The simulator utilized for dynamic modeling is the Delft Advanced Research Terra Simulator (DARTS). The findings demonstrate that reservoirs with moderate sedimentological heterogeneity are actually better sites to store CO2 due to the capacity and effectiveness of the storage.

Overcoming the intermittency problem of renewable energy is an issue that has to be addressed in order to achieve an efficient energy system. Hydrogen has been gaining interests, as green energy carrier, which is included in the energy transition plans of not only the Netherlands, but worldwide. Due to its physical characteristics, large scale storage of hydrogen requires volumes that can only be provided by porous media in the subsurface. Underground Hydrogen Storage (UHS) in depleted gas fields is a large scale storage possibility that is generating attention and increased research. However, it is currently in a Low Technology Readiness Level, meaning that more research, and especially field scale projects are necessary. There is very few literature that tries to use alternative gases as a cushion gas for a UHS. Therefore, this investigation is relevant for the future development of UHS. This investigation will use CMG GEM, a commercial compositional reservoir simulator to model the fluid interactions in the subsurface when hydrogen is stored in depleted gas fields. This will be done by means of a sensitivity analysis, where the hydrodynamic behaviour between hydrogen and possible alternative cushion gases, such as methane, carbon dioxide and nitrogen are studied. Apart from the technical analysis, a simplified economic evaluation is used to calculate a levelized cost to store hydrogen, which will allow for an economic optimized selection of cushion gases in an UHS. The two main constraints for an UHS system are the purity of the extracted hydrogen and the rate at which it is extracted from the subsurface. The results of this investigation show that the mixing of hydrogen with an alternative cushion gas will change drastically based on the degree of the reservoir heterogeneity and the location of the perforated interval. This ever-increasing mixing will have an effect on the capability of the system of delivering pure hydrogen for the expected time.