Tutolo Reactive Transport Group
Our overarching goal is to distill simple, cause-and-effect relationships out of complex Earth systems.
Saline lakes occur in basins and depressions where hydrologic outputs such as evaporation outstrip inputs such as groundwater influx. As the lake waters evaporate, their solutes become increasingly concentrated. If complete dry-out occurs, all that is left behind is an array of interesting, highly soluble salts. This evaporation process can potentially bring together many of the ingredients to originate life on Earth and other rocky bodies, and also support unique extremophile organisms. In our saline lakes work, we use a variety of field monitoring techniques (e.g., fluid sampling, shallow geophysics) and numerical modeling in order to examine the interplays between hydrology, geochemistry, and biology in these unique environments.
Serpentinization as a Reactive Transport Process
Serpentinization, or the hydrothermal alteration of olivine-rich rocks, plays a fundamental role in the biogeochemical and tectonic evolution of the Earth and perhaps many other rocky planetary bodies. Yet, geochemical models still fail to produce accurate predictions of the various modes of serpentinization, which limits our ability to predict a variety of related geological phenomena over many spatial and temporal scales. RTG research is showing that serpentinization and many other hydrothermal processes must be considered in a reactive transport framework whereby fluid, solute, and heat transport are intimately coupled to kinetically-controlled reactions. Simone Pujatti is the primary group member working on this research.
Carbon dioxide storage in sedimentary reservoirs
Abundant pore space is available in spent oil and gas reservoirs and deep saline aquifers for the permanent storage of anthropogenic CO2. Our work in this field focuses on harvesting the potential of converting glauconite-rich greensands formations into siderite, as a safe, permanent CO2 storage mechanism. We are taking a multi-technique approach to this research problem that includes detailed petrographic study of naturally carbonated glauconitic sandstones, experimental determination of the dissolution and carbonation rates of glauconite, and numerical modeling of CO2 injection into and interaction with greensands formations. Qin Zhang and Juan Carlos de Obeso are the primary group members working on this project.
Solid Carbon: A Negative Emissions Technology
Solid Carbon is an ambitious project to permanently and safely sequester carbon dioxide (CO2) as rock. The vision is to extract CO2 directly from the air or ocean. Then, using deep ocean technology powered by ocean-based wind and solar energy, inject the CO2 into the subseafloor basalt, where it mineralizes into solid carbonate rock. RTG researchers are performing experiments and running reactive transport models to evaluate this technology. More info can be found on the Solid Carbon web page. Dr. Adedapo Awolayo, Dr. Christiaan Laureijs, and Dr. Juan Carlos de Obeso are the primary group members working on this project.
Diagenesis and REE deposits in sedimentary rocks
We are working to constrain the records and resources harbored in sedimentary formations. This research focuses on the geochemistry of mineral deposition and transformation in sedimentary rocks, with the intention of constraining societally important problems such as REE deposits and geologic carbon storage. To tackle these research problems, we are using a combination of laboratory experiments, geophysical and geochemical observations in the field, and reactive transport modeling. Qin Zhang and Cameron Wood are the primary group member working in this field.
Silicate mineral growth kinetics from ambient to hydrothermal conditions
Mg-silicate minerals, such as sepiolite, lizardite, chrysotile, and talc, form in an amazing variety of Earth environments, ranging from alkaline lakes to seafloor hydrothermal systems. Importantly, they are also a primary constituent of the scales that form in geothermal wells and steam production equipment. To constrain the solubilities of these various minerals and the rates at which they from from solution, we are running batch and flow-through experiments at temperatures up to 350°C. Dr. Yury Klyukin and Ian Fleming are the primary group members working on this project.
Geothermal energy extraction in Canada
Through collaboration with Steve Grasby and the Geologic Survey of Canada, we are investigating controls on basement permeability and the hydrothermal history of the Williston Basin in order to evaluate the potential for geothermal heat extraction from igneous rocks of Canada's geological "basement". We are using a combination of drill core characterization and reactive transport modeling to advance this project. Taylor Smith is the primary group member working on this project.
PEACH and Calgary Climate Solutions
With the PEACH technology, the Calgary Climate Solutions team is using electrochemistry to manipulate seawater alkalinity and capture CO2 on a global scale. The team has diverse skills and origins but is committed to “research, develop, and if appropriate, test and deploy socially desirable solutions for large scale carbon dioxide removal”, especially ones that safely amplify natural geochemical processes of carbon dioxide removal from the atmosphere. Such projects are not merely technical in nature but crucially also have to be acceptable to society, so policy and governance and finance are as critical a part of design and construction as science and engineering. More about this, and other Calgary Climate Solutions projects with which RTG researchers are involved can be found here.
Although a primary component of our research involves numerical modeling using software such as the ever-useful Geochemist's Workbench and the reactive transport simulator PFLOTRAN, quite a significant amount of our efforts are directed towards performing experiments in the lab and characterizing field samples, particularly drill cores from the International Ocean Discovery Program (IODP). To characterize field and experimental samples, we employ a range of techniques. These include high resolution X-Ray Computed Tomography (XRCT) at laboratory and synchrotron sources; we maintain high performance visualization and processing computer and specialized software for handling these large data sets. In addition, we often utilize combined Small and Ultra Small Angle Neutron Scattering ((U)SANS) at the NIST Center for Neutron Research (NCNR), ISIS Neutron Source or at the Institut Laue-Langevin. We have also been using X-ray Absorption Near-Edge Structure (XANES) at Brookhaven National Laboratory (NSLS-II) and Diamond Light Source to constrain oxidation states of Fe in our samples. We have recently added a Horiba Xplora Plus Raman Microscope and a Triple Quadrupole ICP-MS to our lab facilities; both are open for use. We also often make use of a wide variety of mineralogical, chemical, and (non-traditional) stable isotopic characterization tools available here at Calgary and through collaborations with colleagues. See Lab page for more information.