Presentation materials
We developed a new methodology to compute hydraulic transmissibility between karst-conduits and rock matrix in carbonate reservoirs. Such a parameter quantifies the mass exchange between these two geological objects and can be explored in EDKM-type models (Embedded Discrete Karst Model) via non-neighboring connections. The upscaling procedure adopted hinges on the karst index concept, whose...
Information about sub-surface formations is typically scarce and plagued by uncertainties. Especially when dealing with fractured formations, this strongly impacts the predictive power of numerical simulations. Isolated fractures for example may represent long-ranging highly conductive flow conduits having a strong impact on flow and transport. Furthermore, as fractures can reach extensions...
For deep fractured-vuggy carbonate reservoirs, foam flooding is an effective oil recovery method. However, the connectivity and anisotropy of the fractured-vuggy network affect the plugging performance of foam and the ability to adjust the displacement profile. Therefore, it is necessary to conduct a comprehensive investigation on the migration characteristics of foam, in order to provide...
Understanding material failure is critical for designing stronger and lighter structures by identifying weaknesses that could be mitigated, predicting the integrity of engineered systems under stress to prevent unexpected breakdowns, and evaluating fractured subsurface reservoirs to ensure the long-term stability of the reservoir walls, fluid containment, and surrounding geological formations....
The hydraulic properties of rock fractures are of considerable interest in several areas of engineering applications such as geothermal energy utilization, radioactive waste management, CO2 sequestration, and enhanced oil recovery in naturally fractured reservoirs. Natural rock fractures exhibit the contact-area characteristic due to shearing or normal-compressing processes. This work develops...
In this work, we have studied numerically the fracture initiation conditions induced by non-Newtonian polymer solution in the granular media. Computational Fluid Dynamics (CFD) coupled with the Discrete Element Method (DEM) technique is used to model fluid flow through porous media. The power law used to describe the polymer solution flow. The associated parameters are considered in the drag...
Predicting what permeability enhancements are feasible in a geothermal system (EGS) and the potential seismic activity they may trigger is challenging. Geomechanical simulations are computationally expensive because they require a discretized fracture network with a relevant level of complexity and a quantification of frictional sliding and tensile opening of individual fractures therein. Yet,...
Despite the amount of research on flow and transport in single fractures and fracture networks, there is a gap in knowledge between the field data describing natural fractures and the models that represent them. Natural fracture networks exhibit ranges of fracture lengths, connectivity, and aperture distributions, which directly affect the flow and transport behavior within the network. The...
The Thresholded Gaussian Fields (TGF) algorithm [1] creates realistic realizations of 2D and 3D random media by generating a random topography and then thresholding it. The result is a synthetic volume composed of compact sub-volumes corresponding to different material types. TGF has been used to simulate porous media ranging from pore spaces to aquifers composed of multiple facies. The...
Hydraulic fracturing is a key technology for increasing oil and gas production, developing geothermal energy, and releasing coal from the roof. However, there is an irreconcilable scale contradiction between the research results of laboratory studies at the meter scale and the field fracturing technology requirements at the hundred-meter scale. Therefore, it is urgent to establish a mesoscale...
Coastal erosion is a growing concern for many coastal regions worldwide, and salt weathering has been identified as a contributing factor to this phenomenon. This research focuses on the ongoing erosion of the French Basque Country coastline, particularly between the connecting sections of Saint-Jean-de-Luz and Hendaye which are characterized by Santonian flysch rock cliffs.
The objective of...
Mineral dissolution during groundwater flow is a crucial phenomenon that has received continued interest for decades as a main drive of various subsurface processes, such as carbon mineralization, karstification, and the formation of complex rock patterns in caves. In fractured media and dissolving porous media, fluid inertia can play an important role in shaping fluid flow and dissolution...
To achieve the goal of limiting the global temperature increase to below 2°C and avoid the adverse effects of climate change, the removal of CO2 from the atmosphere requires the simultaneous application of carbon capture, utilization, and storage (CCUS) methods. Among these, carbon mineralization is a promising approach that can securely trap a substantial amount of CO2. Ultramafic rocks, such...
Chemical reactions induced by fluids that are out of chemical equilibrium with the minerals on fracture surfaces lead to mineral dissolution and/or precipitation along fracture surfaces and alterations in the fracture aperture. Incorporating the influence of localized chemical alterations into continuum models requires effective constitutive models that relate changes in mechanical aperture to...
Numerical modeling of coupled thermal, hydraulic, and mechanical (THM) processes is crucial for understanding and capturing the complex interactions in enhanced geothermal systems (EGS). We describe the development of the numerical approach for coupling those processes to improving the predictive capabilities for the EGS testbed site, part of the Center for Understanding Subsurface Signals and...
Fractures and fracture networks are critical pathways for subsurface flow and reactive transport in rock. In particular, fracture intersections, where fluids with different properties mix and react, serve as biogeochemical reaction hotspots. Recent studies have highlighted the importance of intersection geometry in influencing mixing dynamics. Although geologic fractures are subjected to...
Investigating gas-liquid flow in porous media is of great importance, particularly in the fields of enhanced oil and gas recovery and geological sequestration. CO2 near-miscible flooding is considered an effective method for enhancing oil recovery. However, there is a lack of pore-scale analyses on the flow dynamics and interfacial properties involved in this process, such as wettability,...
Gas hydrates represent a vast and clean energy source. However, during the depressurization extraction process, the migration and deposition of fine particles can lead to clogging of flow channels, which restricts commercial production. Although some continuum-scale theoretical models for fine particle migration in hydrate reservoirs have been developed, they fail to account for inter-particle...
Recently, Krauklis waves (Krauklis, 1962)—guided waves that propagate mostly as pressure pulses within fluid-filled, high-permeability fractures—have gained attention as a geophysical tool for subsurface fracture characterization. Strongly dispersive velocity and attenuation of these waves are sensitive to the hydraulic conductivity (permeability) of the fractures. This property may give...
Accurately modelling fracture networks in low-permeability formations like caprocks requires an understanding of the complexity of a single fracture geometry and its impact on flow. Fractures are often oversimplified as planar, ignoring the variability that influences flow behaviour. Most fracture geometry research focuses on granites and sandstones, while caprock fractures remain...
Humanity's innate drive for discovery has fueled exploration beyond Earth's boundaries, from landing on the Moon to ambitious missions targeting other planets and celestial bodies. Achieving these goals requires meticulous planning and engineering. Engineering uncertainty tolerances are gaining importance, mainly as mission objectives demand transporting larger payloads, such as...
Hydraulic fracturing is a technique that involves injecting fluids into rock formations at high pressure to create cracks or hydro-fractures. While hydro-fracture can occur naturally during seismic events, hydraulic fracturing is a human-engineered process used to increase the permeability of low-permeability rock formations. This technique is widely applied in engineering applications such as...
