Effectiveness of X-ray micro-CT applications upon mafic and ultramafic ophiolitic rocks

3D Quantification of Pore Networks and Anthropogenic Carbon Mineralization in Stacked Basalt Reservoirs

“…However, the segmentation of the carbonate nodules in SWCs of 839.7 and 874.7 m depths was difficult to quantify due to the similar grayscale colors between the carbonate nodules and the high-density phases (ilmenite, hematite, and magnetite) ,− disseminated in the basalt matrix. Although halite (NaCl) has been shown to stand out in X-ray tomographic imaging, this phase has not been previously observed in CRB samples. , It is difficult to discriminate between minerals with similar attenuation coefficients and/or densities, especially when the mineral has a variable composition that cannot be binned into a narrow grayscale range. , Overall, the carbonate nodules were attached to pore walls and heterogeneously distributed within the core as many pores did not host nodules. We suggest that heterogeneous distribution of carbonate nodules is a consequence of pore-scale fluid chemistry differences, especially those that may arise during nucleation and growth processes that concentrate reactants within a growing crystallite assemblage.…”

“…6,27 It is difficult to discriminate between minerals with similar attenuation coefficients and/or densities, especially when the mineral has a variable composition that cannot be binned into a narrow grayscale range. 9,30 Overall, the carbonate nodules were attached to pore walls and heterogeneously distributed within the core as many pores did not host nodules. We suggest that heterogeneous distribution of carbonate nodules is a consequence of porescale fluid chemistry differences, especially those that may arise during nucleation and growth processes that concentrate reactants within a growing crystallite assemblage.…”

“…X-rays are attenuated while passing through a material following Lambert and Beer’s law, and this attenuation coefficient depends upon the atomic electron density and the bulk material density. X-ray tomographic imaging is a convenient tool for exploring energy dissipation and quantifying the microstructural properties of mafic and ultramafic rocks. ,,− To provide a robust analysis of the postinjection basalt cores, we used XMT imaging to reconstruct 3D volumetric distribution of porosity, carbonate nodules, and other mineral phases.…”

First application of scintillator-based photon-counting computed tomography to rock samples: Preliminary results and prospects

“…Attenuation-contrast X-ray computed tomography (X-ray CT) allows us to observe the external and internal features of objects by analyzing differences in Xray transmission between the different phases/materials composing the object. This technique has been widely used to determine three-dimensional distribution of minerals within the volume of natural and artificial geomaterials both using laboratory-based and synchrotron-based X-ray sources (e.g., Ketcham, 2005;Zandomeneghi et al, 2010;Voltolini et al, 2011;Baker et al, ,2012;Cnudde et al, 2013;Marinoni et al, 2015;Parisatto et al, 2018;Hibiya et al 2019;Pak et al 2019;Selem et al 2021;Giamas et al 2022). X-ray CT measures the linear attenuation coefficients, which are derived from differences in X-ray intensity before and after transmission.…”