InterPore2025

High-resolution computed tomography scanning to assess diagenetic influences on multiphase transport in sandstones

21 May 2025, 15:05

1h 30m

Poster Presentation (MS10) Advances in imaging porous media: techniques, software and case studies Poster

Speaker

Shelby Isom (National Energy Technology Laboratory)

Description

Successful CO2 sequestration in a saline reservoir requires characterizing the geological storage site to develop an understanding of fluid transport behavior for long-term modeling and risk assessment. The Department of Energy is supporting numerous carbon storage field projects across the United States to advance this technology, and the CarbonSAFE San Juan Basin (SJB) project is one of these targeting geologic CO2 sequestration in saline formations of New Mexico. A characterization well for the SJB CarbonSAFE project was drilled in the northwest corner of New Mexico intersecting several potential injectable Jurassic formations including the Entrada and Bluff sandstones.
Entrada and Bluff sandstone core retrieved during drilling of the SJB CarbonSAFE characterization well were subcored into  1” by 2” cylindrical plugs for high-resolution computed tomography (CT) scanning characterization and low-resolution dynamic CT scanning of CO2 injection through brine-filled cores. The high-resolution CT scanning allows for the non-destructive characterization of interconnectivity of pores, identification of bedding structures, and presence and morphology of mineral infilling pores. The dynamic CT scans provide an opportunity to observe the transient behavior of multiphase flow through these structures and understand what features in the natural porous medium influence transport.
This presentation describes the samples from the Bluff Sandstone characterized in collaboration with the SJB CarbonSAFE team. Specifically, several samples that display rare large (~0.15 mm in diameter) high-density minerals and abundant localized calcite cement patches that infill pores. These features were shown to influence the multiphase flow through the cores, with the preferential pathways of CO2 transport occurring in the presence of these features.
When comparing these studies to analyses in the Entrada Sandstone, which do not contain any of these secondary features, the complex morphology and relationship to permeability with diagenesis is illustrated. This study highlights the importance of detailed micro-scale investigations into sandstones, which appear similar in the field but have different petrophysical properties.