Measuring Variations in Rock Mechanical Properties Due to CO2 Injection: Application of Nano-Indentation

Abstract Injecting CO2 into geological formations has become an important process for carbon sequestration to reduce atmospheric CO2 levels and mitigate climate change. Therefore, understanding the impact of CO2 injection on rock mechanical properties is essential for assessing the integrity and safety of storage sites. This study employs nanoindentation to measure variations in rock mechanical properties caused by CO2 injection. Nanoindentation provides localized measurements of hardness and elastic modulus. Results indicate significant alterations of more than 95% reduction in Young's modulus of the carbonate rock samples post-CO2 injection, with implications for the long-term stability of sequestration sites. This research contributes to the development of more accurate models for predicting the mechanical performance of CO2-injected carbonate rocks, ultimately enhancing the safety and efficacy of carbon sequestration and enhanced oil recovery using CO2 efforts.