Graduate Studies


First Advisor

Caroline M. Burberry

Date of this Version

Summer 7-28-2023

Document Type



Fleagle, S. (2023). Reservoir Characterization of Stacked Carbonates of the Pennsylvanian and Permian in Western Nebraska for Potential Carbon Dioxide Storage (Master's Thesis, University of Nebraska, Lincoln, Nebraska, USA)


A THESIS Presented To the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirement For the Degree of Master of Science, Major: Earth and Atmospheric Sciences, Under the Supervision of Professor Caroline M. Burberry. Lincoln, Nebraska: June 2023

Copyright © 2023 Samuel Fleagle


In Nebraska, carbon dioxide emissions come from burning fossil fuels (approximately 15 million tons of CO2 per year) and from ethanol plants (approximately 4 million tons of CO2 per year). Carbon capture and storage (CCS) is therefore vital to improve the air quality in Nebraska and to enable these industries to operate. The study area for this project covers presently unevaluated portions of the subsurface of Western Nebraska. The hypothesis is that there is extensive storage space for carbon dioxide, specifically in the stacked carbonates of the Pennsylvanian system. The aim is to define a reservoir space with 50 million tons of storage capacity injected over the span of a decade, i.e., the CarbonSAFE goal. Using well call outs (available through the Nebraska Oil and Gas Conservation Commission), in combination with borehole geophysical datasets, lithostratigraphic surfaces were generated for use in stratigraphic modeling of the subsurface. Rock core was logged and sampled to further understand the lithology and obtain geomechanical properties of reservoir and seal units. Using volumes extracted from stratigraphic models generated using lithostratigraphic surfaces and the geomechanical data, numerical simulations were run using the National Energy Transition Lab’s (NETL) CO2-Screen, a Monte Carlo-based package that generates a probabilistic range of storage volumes.

The results of numerical simulations of storage potential for a model of a subregion of interest in Lincoln County, Nebraska have probabilistic estimates ranging from 1.8Mt/mile2 to 5.3Mt/mile2 (0.713Mt/km2 to 2.081Mt/km2). These results demonstrate that the subregion is viable and promising for a further stage of data gathering, including seismic surveys and the drilling of a stratigraphic test well to completely evaluate the reservoir units. There is evidence for strong primary and secondary seals overlying the potential reservoir units. The subsurface storage of CO2 is critical to global efforts to reduce the effects of greenhouse gas-induced climate change. Reducing emissions will improve local air quality and aid in the larger goal of curtailing emissions of greenhouse gases to mitigate the impacts of climate change.

Advisor: Caroline M. Burberry