Effect of Biogeomechanical Altered Properties on Geologic Carbon Storage in Unconventional Reservoirs

Abstract:

Geologic Sequestration (GS) is part of a process known as carbon capture, utilization, and storage (CCUS); used across the world to mollify extreme weather events (global warming) as a result of CO₂ emissions and improve energy production. In this study, we experimentally and analytically investigate the impact of microbially-altered mechanical properties on geologic carbon storage in unconventional reservoirs, using a cultured bacteria solution with a novel growth nutrient, and shale rock specimens from Eagle Ford, Marcellus, and Niobrara formations. Firstly, we obtained the physical, mineralogical, and mechanical properties of untreated shale rock specimens. Secondly, we treated and cultivated the core samples with the cultured bacteria solution at specific temperature, time, and growth conditions. Further, we obtained the altered mineralogical and mechanical properties of the shale rock specimens impacted by the microbes. Lastly, we show the impact of microbially-modified mechanical properties on underground storage integrity of CO₂ in unconventional shale reservoirs. Our results suggest that in shale reservoirs, biogeomechanical modifications can enhance the long-term integrity of geologic sequestration of atmospheric CO₂, by mitigating any deep subsurface potential leakage to the atmosphere.