Tutolo, BenjaminMayer, BernhardZhang, Qin2022-05-262022-05-262022-05Zhang, Q. (2022). From Greensands to Green Technology: Examination of Carbon Dioxide Storage Potential in Glauconitic Sandstones (Doctoral thesis, University of Calgary, Calgary, Canada). Retrieved from https://prism.ucalgary.ca.http://hdl.handle.net/1880/114695Glauconite is a divalent cation-bearing mineral abundant in sedimentary rocks and hydrocarbon reservoirs worldwide, and it may be important for ongoing efforts to geologically store anthropogenic CO2. Since glauconite naturally contains both Fe(II) and Fe(III) in its mineral structure, it can also be leveraged to constrain paleoenvironmental redox conditions. Nevertheless, because of its complex mineralogy and redox sensitivity, thermodynamic and kinetic properties of glauconite have been difficult to constrain. This thesis has been devoted to fill this significant knowledge gap. Chapter 2 contains a detailed evaluation of the mechanisms through which carbonate minerals naturally replace glauconite during diagenesis of glauconitic sandstones from the Mannville Group in Alberta, Canada. Using a combination of petrological and geochemical analyses, we show that glauconite carbonation is a reduction-facilitated, coupled glauconite recrystallization and siderite precipitation reaction, which is accompanied by a significant reduction of Fe. These results suggest that geochemical conditions, most importantly, temperature, partial pressure of CO2, and fluid redox state were thermodynamically favorable for glauconite carbonation during burial diagenesis of Mannville Group glauconitic sandstones. Chapter 3 quantifies the far-from-equilibrium rates of glauconite dissolution using a novel experimental apparatus specifically designed to explore mineral dissolution kinetics under strictly anaerobic conditions. Steady-state glauconite dissolution rates were measured at varying pH from 1.7 to 11.2 and temperature from 24 to 80 °C. The experimental results show stoichiometric or close-to-stoichiometric glauconite dissolution for Fe, Mg and Si. In comparison to previous studies, we emphasize that the mechanism of glauconite dissolution is determined by redox condition and temperature, and the dissolution rates are pH-dependent in acidic conditions and pH-independent in natural to basic pH. Chapter 4 uses calculations based on 11,652 well logs to show that glauconitic sandstones offer significant and previously overlooked potential for sedimentary reservoir-based mineral carbonation. Our results demonstrate that hundreds of gigatons of CO2 could be sequestered by carbonating the immense quantity of glauconite underlying Alberta, Canada alone. Together, these findings suggest that glauconite had been underestimated both in terms of availability and reactivity, and these new findings provide important insights to re-evaluate CO2 storage in sedimentary basins.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.glauconitesideritemineral carbonationCO2 storageclimate solutionmineral kineticsEducation--Sciencesdoctoral thesis10.11575/PRISM/39801