@article{wang_dalton_fan_guo_mcclure_crandall_chen_2023, title={Deep-learning-based workflow for boundary and small target segmentation in digital rock images using UNet++ and IK-EBM (vol 215, 110596, 2022)}, volume={221}, ISSN={["2949-8910"]}, DOI={10.1016/j.petrol.2022.111306}, journal={GEOENERGY SCIENCE AND ENGINEERING}, author={Wang, Hongsheng and Dalton, Laura and Fan, Ming and Guo, Ruichang and McClure, James and Crandall, Dustin and Chen, Cheng}, year={2023}, month={Feb} }
 @article{dalton_rasanen_voss_seppanen_pourghaz_2023, title={Investigating the use of electrical capacitance tomography to image rapid transient moisture flow through cracks in concrete}, volume={140}, ISSN={["1873-393X"]}, DOI={10.1016/j.cemconcomp.2023.105070}, abstractNote={In this paper, we investigate the feasibility of electrical capacitance tomography (ECT) to image rapid three-dimensional (3D) moisture transport in damaged portland cement mortar and concrete. ECT is a tomography method that uses inter-electrode capacitance measurements to reconstruct the internal 3D distribution of the electrical permittivity which carries contrast with respect to moisture content. In the experimental study, ECT measurements were performed with a reservoir placed directly on the crack in each specimen to promote rapid moisture transport to test the high temporal resolution capabilities. An electrode array connected to an electrical tomography device was used to conduct moisture transport measurements in cracked specimens at a temporal resolution as high as 0.7 s. The results of this study illustrate that ECT can be used to detect rapid moisture transport through various crack patterns and capture the flow path of water around coarse aggregates with potential use for field monitoring.}, journal={CEMENT & CONCRETE COMPOSITES}, author={Dalton, Laura E. and Rasanen, Mikko and Voss, Antti and Seppanen, Aku and Pourghaz, Moe}, year={2023}, month={Jul} }
 @article{wang_dalton_fan_guo_mcclure_crandall_chen_2022, title={Deep-learning-based workflow for boundary and small target segmentation in digital rock images using UNet plus plus and IK-EBM}, volume={215}, ISSN={["1873-4715"]}, DOI={10.1016/j.petrol.2022.110596}, abstractNote={Three-dimensional (3D) X-ray micro-computed tomography (μCT) has been widely used in petroleum engineering because it can provide detailed pore structural information for a reservoir rock, which can be imported into a pore-scale numerical model to simulate the transport and distribution of multiple fluids in the pore space. The partial volume blurring (PVB) problem is a major challenge in segmenting raw μCT images of rock samples, which impacts boundaries and small targets near the resolution limit. We developed a deep-learning (DL)-based workflow for accurate and fast partial volume segmentation. The DL model's performance depends primarily on the training data quality and model architecture. This study employed the entropy-based-masking indicator kriging (IK-EBM) to segment 3D Berea sandstone images as training datasets. The comparison between IK-EBM and manual segmentation using a 3D synthetic sphere pack, which had a known ground truth, showed that IK-EBM had higher accuracy on partial volume segmentation. We then trained and tested the UNet++ model, a state-of-the-art supervised encoder-decoder model, for binary (i.e., void and solid) and four-class segmentation. We compared the UNet++ with the commonly used U-Net and wide U-Net models and showed that the UNet++ had the best performance in terms of pixel-wise and physics-based evaluation metrics. Specifically, boundary-scaled accuracy demonstrated that the UNet++ architecture outperformed the regular U-Net architecture in the segmentation of pixels near boundaries and small targets, which were subjected to the PVB effect. Feature map visualization illustrated that the UNet++ bridged the semantic gaps between the feature maps extracted at different depths of the network, thereby enabling faster convergence and more accurate extraction of fine-scale features. The developed workflow significantly enhances the performance of supervised encoder-decoder models in partial volume segmentation, which has extensive applications in fundamental studies of subsurface energy, water, and environmental systems.}, journal={JOURNAL OF PETROLEUM SCIENCE AND ENGINEERING}, author={Wang, Hongsheng and Dalton, Laura and Fan, Ming and Guo, Ruichang and McClure, James and Crandall, Dustin and Chen, Cheng}, year={2022}, month={Aug} }
 @article{dalton_lamanna_jones_pour-ghaz_2022, title={Does ITZ Influence Moisture Transport in Concrete?}, ISSN={["1573-1634"]}, DOI={10.1007/s11242-022-01826-z}, journal={TRANSPORT IN POROUS MEDIA}, author={Dalton, Laura E. and LaManna, Jacob M. and Jones, Scott and Pour-Ghaz, Mohammad}, year={2022}, month={Jul} }
 @article{guo_dalton_crandall_mcclure_wang_li_chen_2022, title={Role of heterogeneous surface wettability on dynamic immiscible displacement, capillary pressure, and relative permeability in a CO2-water-rock system}, volume={165}, ISSN={["1872-9657"]}, DOI={10.1016/j.advwatres.2022.104226}, abstractNote={Surface wettability is one of the major factors that regulate immiscible fluid displacement in porous media. However, the role of pore-scale wettability heterogeneity on dynamic immiscible displacement is rarely investigated. This study investigated the impact of pore-scale wettability heterogeneity on immiscible two-fluid displacement and the resulting macroscopic constitutive relations, including the capillary pressure-water saturation (Pc-Sw) and relative permeability curves. A digital Bentheimer sandstone model was obtained from X-ray micro-computed tomography (micro-CT) scanning and the rock surface wettability fields were generated based on in-situ measurements of contact angles. A graphics processing unit-accelerated lattice Boltzmann model was employed to simulate the immiscible displacement processes through the primary drainage, imbibition, and second drainage stages in a CO2-water-rock system. We found that pore-scale surface wettability heterogeneity caused noticeable local supercritical CO2 (scCO2) and water redistribution under less water-wet conditions. At the continuum scale, the Pc-Sw curves under the heterogeneous wetting condition were overall similar to those under the homogeneous wetting condition. This is because the impact of local wettability heterogeneity on the large-scale Pc-Sw curve was statistically averaged out at the entire-sample scale. The only difference was that heterogeneous wettability led to a negative entry pressure at the primary drainage stage under the intermediate-wet condition, which was caused by local, scCO2-wet surfaces. The impact of pore-scale wettability heterogeneity was more noticeable on the relative permeability curves. Particularly, the variation of the scCO2 relative permeability curve in the heterogeneous wettability scenario was more significant than that in the homogenous wettability scenario. This suggests that pore-scale wettability heterogeneity enhances the coalescence and snap-off behaviors of scCO2 blobs. This is the first study that systematically investigated the role of pore-scale wettability heterogeneity on dynamic immiscible displacement and associated Pc-Sw curves in complicated, three-dimensional porous media.}, journal={ADVANCES IN WATER RESOURCES}, author={Guo, Ruichang and Dalton, Laura and Crandall, Dustin and McClure, James and Wang, Hongsheng and Li, Zhe and Chen, Cheng}, year={2022}, month={Jul} }
 @article{dalton_crandall_pour-ghaz_2022, title={Supercritical, liquid, and gas CO2 reactive transport and carbonate formation in portland cement mortar}, volume={116}, ISSN={["1878-0148"]}, DOI={10.1016/j.ijggc.2022.103632}, abstractNote={In this study, we investigate carbonate formation and reactive transport rate in variably saturated portland cement mortars when high concentrations of gas, liquid, or supercritical CO2 flow through their pore network. X-ray computed tomography completed during CO2 flow is used to quantify the microstructural evolution as the mortar carbonates. After in situ tests, higher resolution scans, thermogravimetric analysis, and desorption isotherm analysis are performed to further quantify microstructural changes. We found that at dry conditions supercritical CO2 moves more rapidly through the pore space and precipitates more carbonates than liquid or gas CO2. However, at 50% degree of saturation (DOS) the CO2 state did not affect the rate of transport in that each specimen exposed to a different CO2 state carbonated within the first hour of CO2 exposure. When the pore space is at 50 or 100% DOS, supercritical CO2 did not react with hydration products more rapidly nor did it result in more carbonate formation during exposure compared to gas or liquid CO2. The amount of Ca(OH)2 that contributes to CaCO3 formation is correlated to the DOS. For the mortar composition analyzed, Ca(OH)2 contributes to approximately 40% of the carbonates formed in the 50% DOS specimens and 15% in the 100% DOS specimens. In other words, as the amount of moisture in the pore space increases, phases other than Ca(OH)2 contribute to more than 50% of the total CaCO3 formed.}, journal={INTERNATIONAL JOURNAL OF GREENHOUSE GAS CONTROL}, author={Dalton, Laura E. and Crandall, Dustin and Pour-Ghaz, M.}, year={2022}, month={May} }
 @article{dalton_jarvis_pour-ghaz_2020, title={The Effect of Gas Solubility on the Secondary Sorption in a Portland Cement Mortar Observed by X-ray CT}, volume={133}, ISSN={["1573-1634"]}, DOI={10.1007/s11242-020-01429-6}, number={3}, journal={TRANSPORT IN POROUS MEDIA}, author={Dalton, Laura E. and Jarvis, Karl and Pour-Ghaz, Mohammad}, year={2020}, month={Jul}, pages={397–411} }