I work at the intersection of geoscience and geoengineering to address problems related to energy and the environment. Current focus areas are:
Geologic Fault Zone Characterization
Forecasting of Subsurface Multiphase Flows
Induced Seismicity in Geoenergy Development
A summary of work I have carried out in these areas is provided below:
FAULT zone characterization
Accurate prediction of subsurface phenomena and safety in subsurface technologies often requires a quantitative understanding of the hydraulic and mechanical behavior of geologic faults. This is difficult to achieve, given the heterogeneous nature of faults and our limited ability to image them and measure their physical properties. Current models of hydraulic and mechanical properties of fault zones are strong simplifications of reality, and are often based on empirical correlations derived from laboratory tests.
Our work in this area has focused on normal faults in soft siliciclastic basins, with the goal of quantifying uncertainty in fault core permeability and anisotropy. This geologic setting is of particular interest for geologic carbon storage, given the ability of poorly lithified sediments to accommodate significant deformation ductilely.
Next, I would like to extend this work to modeling multiphase flow properties, and target different geologic settings.
Relevant Publications
L. Saló-Salgado, J.S. Davis, and R. Juanes: Fault permeability from stochastic modeling of clay smears, Geology, 51(1), 2023. DOI: 10.1130/G50739.1
Links: [Paper (Gold OA)][Supplement: Description of PREDICT][Code]
Effect of stratigraphic proportion of clay on fault core permeability.
Top panel shows more fragmented clay smear, and higher permeability.
Numerical simulation of CO2 injection in the Miocene section, Gulf of Mexico.
Direct comparison between experiments of CO2 injection (left column) and numerical simulations (gas saturation, middle, and CO2 concentration, right).
forecasting co2 migration during GEOLOGIC Carbon dioxide SEQUESTRATION
Carbon capture and geological storage (CCS) is a technology that can be deployed at scale to mitigate CO2 emissions as we transition to a sustainable energy system. To evaluate the feasibility of geologic CO2 storage in a given location, one of the key tools is numerical modeling. These models inform us about the migration of CO2 in the subsurface, and are regularly used to make forecasts and inform decisions.
Questions we have addressed in this area include:
What is the hazard of CO2 migration through geologic faults?
How accurate are subsurface models of CO2 storage?
I am now collaborating in two projects focused on developing neural network models for uncertainty quantification of multiphase flows in porous media.
Relevant Publications
L. Saló-Salgado, M. Haugen, K. Eikehaug, M.A. Fernø, J.M. Nordbotten, R. Juanes: Direct comparison of numerical simulations and experiments of CO2 injection and migration in geologic media: Value of local data and predictability. Transport in Porous Media, 151, 1199-1240, 2024. DOI: 10.1007/s11242-023-01972-y. Links: [Publisher version][accepted PDF]
L. Saló-Salgado, J. A. Silva, L. Lun, C. M. Rogers, J. S. Davis, R. Juanes: Assessing CO2 migration within faults during megatonne-scale geologic carbon dioxide storage in offshore Texas. Submitted for publication.
H. Lu, L. Saló-Salgado, Y. Marzouk, R. Juanes: Uncertainty Quantification of Fluid Leakage and Fault Instability in Geologic CO2 Storage. Submitted for publication. Preprint available at: arXiv:2411.08039
INDUCED SEISMICITY in subsurface energy technologies
Injection and extraction of fluids in the subsurface can generate earthquakes. This is because these activities modify fluid pressures and subsurface mass distribution, leading to changes in the stress state and the stability of geologic faults. Mitigating the hazard of induced seismicity is critical in subsurface applications including wastewater disposal, geothermal energy, geologic carbon sequestration or hydrogen storage.
My first work in this area focused on the Castor Underground Gas Storage, where three M 4 earthquakes occurred as a result of cushion gas injection. More recently, I have coauthored a study evaluating the impact of well placement on fault destabilization during CO2 sequestration in the Miocene section, Gulf of Mexico, using coupled flow and geomechanics. I am currently mentoring undergraduate student Runako Gentles, who is working on classification of induced earthquakes using machine learning.
This area will be the primary focus of my postdoctoral research, which focuses on understanding the impact of reservoir operations on earthquake occurrence in Los Angeles Basin.
Relevant Publications
J. A. Silva, L. Saló-Salgado, J. Patterson, G. R. Dasari, R. Juanes: Assessing the viability of CO2 storage in offshore formations of the Gulf of Mexico at a scale relevant for climate-change mitigation. International Journal of Greenhouse Gas Control, 126(6), 103884, 2023. DOI: 10.1016/j.ijggc.2023.103884
L. Saló, T. Frontera, X. Goula, L.G. Pujades, and A. Ledesma: Earthquake static stress transfer in the 2013 Valencia Gulf (Spain) seismic sequence, Solid Earth, 8, 857-882, 2017. DOI: 10.5194/se-8-857-2017.
Links: [Publisher version (OA)]
Obtained focal mechanisms for the eight main events in the 2013 Castor UGS seismic sequence (a), and 3-D view of the fault model used to calculate static stress transfer during the seismic sequence (b).