Investigating the Effects of Geologic CO2 Sequestration on Microbial Physiology, Metabolism and Functionality.
EMSL Project ID
45400
Abstract
The injection of greenhouse gases into deep geologic formations offers a promising strategy for reducing emissions into the atmosphere that contribute to global warming. The injection of CO2 as a supercritical phase (scCO2) impacts the biogeochemical environment, and can induce mineral dissolution and re-precipitation, as demonstrated for a range of systems. However, the impacts of these injection processes on indigenous microbial communities are poorly understood. Field trials have reported continued microbial activity following scCO2 injection, suggesting that bacteria are able to tolerate the changing geochemical conditions associated with increased concentrations of CO2. If geologic CO2 sequestration is to offer a realistic option for limiting emissions, then the microbial processes that may occur in storage reservoirs needs to be better understood; while bacteria may potentially improve caprock integrity via enhanced mineral precipitation and biomass accumulation, methanogenic processes may also be stimulated which are less desirable. We propose a multi-disciplinary study that will utilize a suite of novel analytical tools to determine the effects of scCO2 on the physiology, metabolism, and function of bacteria. High pressure NMR will be utilized to track the metabolic potential of both model subsurface organisms, and novel bacteria isolated from the deep subsurface, under increasing CO2 concentrations. These studies will be tied to microscopic investigations (TEM) to reveal visual cellular changes associated with scCO2 exposure. Finally, combined global proteogenomic and transcriptomic analyses will be applied to samples to determine functional responses to increasing CO2, and identify potential regulatory mechanisms that operate at the RNA level. Parallel studies will probe the impact of biological material (peptides, proteins) on enhanced mineral precipitation under supercritical conditions. Following the successful application of these techniques to bacterial systems, we propose investigating responses associated with methanogenic archaeal strains under similar conditions. These investigations will offer a unique dataset on the potential responses of indigenous microorganisms to scCO2 injection, and the impacts of these interactions on the effectiveness and feasibility of geologic CO2 sequestration.
Project Details
Project type
Exploratory Research
Start Date
2011-08-01
End Date
2012-08-05
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members