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Mackey, Paige

Publications and source records attributed to Mackey, Paige.

6 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

Characterization of Core from Sanford Underground Research Facility

Computed tomography and special core analysis data associated with the technical report series document Computed Tomography Scanning and Geophysical Measurements of the Enhanced Geothermal Systems (EGS) Collab SURF Core. Paronish, T.; Mackey, P.; Schmitt, R.; Crandall, D.; Moore, J.; Brown, S.; Roggenthen, W.; Schwering, P. C.; Dobson, P. F.; Kneafsey, T. Computed Tomography Scanning and Geophysical Measurements of the Enhanced Geothermal Systems (EGS) Collab SURF Core; DOE.NETL-2021.2866; NETL Technical Report Series; U.S. Department of Energy, National Energy Technology Laboratory: Morgantown, WV, 2022; p 76.

computed tomography↗
DOE OSTI2021

Gouge formation and dilation impacts to flow during fracture shearing

We report flow in fractures is of critical importance to fluid flow in low-permeability shales, particularly when they restrict vertical migration from reservoirs. The Mt. Simon Sandstone is a target for geologic CO 2 sequestration and the overlying Eau Claire Formation is the sealing formation capping this reservoir. The lower Eau Claire, a primary barrier to upward migration of CO 2 from the Mt. Simon, is lithologically heterogenous with a mixture of sandstone and shale. We use a series of flow-through experiments on fractured samples from the Eau Claire to document the morphological changes taking place in the fracture and surrounding rock as it is sheared in a stepwise fashion. The samples were imaged using computed tomography after each shearing episode and flow resistance was calculated based on the pressure differential across each core. We found that gouge accumulations in the fracture plane led to specific instances of self-sealing behavior despite the fact that most samples increased in average fracture aperture and transmissivity. Gouge limited the increase or, in some cases, decreased flow through these samples. Fractures adjacent to shale-rich zones and concordant with bedding were more likely to show evidence of self-sealing, while increased sandstone content and fracture orientation perpendicular to bedding planes was more likely to result in fracture dilation and fracture permeability increases. Reactivation and shearing of vertical fractures in lithologically heterogenous caprocks is more likely to pose risks to long term CO 2 storage scenarios.

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