Contribution of neutron tomography to 3D heterogeneity analysis of granitic rocks

Abstract

Volumetric studies of mica spatial distribution inside samples of Westerly and Czech granites (Mrakotin, Liberec, and Brno syenite) were performed using a neutron tomography method. A significant difference in the neutron attenuation coefficients of mica and other rock-forming minerals of the granites studied yielded a large neutron radiography contrast and, as a result, allowed us to perform a detailed analysis of three-dimension structural data based on the neutron tomography reconstruction procedure. The morphology and spatial distribution of the mica phase within studied granites were obtained. Tomography data were compared to results provided by other experimental methods commonly used in rock mechanics research such as optical and electron microscopy, as well as ultrasonic shear-wave measurements. The benefits and limitations for application of the neutron tomography method for studies of granite like rocks are discussed.

Structural Features of the Fragments from Cast Iron Cauldrons of the Medieval Golden Horde: Neutron Tomography Data

“…The obtained stereoplots (Figure 7a-d) are non-uniform, which evidences the presence of the shape fabric [57][58][59]. Such configurations of preferred orientations in the small pores inside cast iron fragments can indicate some alignment of pores along the curved forms on the fragments surfaces, which is typical for the shapes of cast iron fragments.…”

Non-destructive analysis of materials by neutron imaging at the TITAN facility

“…Using these methods, the internal structure of pyrite-rich rock was studied. Due to the highly penetrating ability of neutrons, it is possible to obtain a neutron image of the investigated materials of a rather large size [42]. Based on the difference in the thermal neutron attenuation coefficient of rock constituents and the use of modern mathematical algorithms for the analysis of three-dimensional (3-D) image data, it was possible to obtain the spatial distribution of pyrite in studied rock sample taken from place of ejections of mud volcanoes in Azerbaijan.…”

Neutron Tomography Studies of Two Lamprophyre Dike Samples: 3D Data Analysis for the Characterization of Rock Fabric

“…From this point of view, X-ray and neutron tomography methods can, potentially, provide a full 3D picture of the spheroidal texture, expressed by spatial distribution, particle morphology and shape orientation distribution of different kinds of inclusions inside the dike volume. It has been shown [ 10 , 11 , 12 , 13 ] that neutron radiography and tomography are efficient methods in studying the internal structure of different igneous and metamorphic rocks, as well as construction and archeological materials. In the case of rock material, the high penetration ability of neutrons, as compared to X-ray, allows one to measure rather large volumes, while high contrast between hydrous and anhydrous minerals in neutron images [ 10 , 14 ] provides the necessary conditions for phase segmentation.…”

“…It has been shown [ 10 , 11 , 12 , 13 ] that neutron radiography and tomography are efficient methods in studying the internal structure of different igneous and metamorphic rocks, as well as construction and archeological materials. In the case of rock material, the high penetration ability of neutrons, as compared to X-ray, allows one to measure rather large volumes, while high contrast between hydrous and anhydrous minerals in neutron images [ 10 , 14 ] provides the necessary conditions for phase segmentation. This is of particular importance, since igneous dikes are relatively dense rocks in the groundmass, composed of amphiboles and feldspars, while the spheroidal inclusions, which may form the flow-related texture, are presented by quartz, feldspars, calcite, and other minerals, rather transparent for neutrons.…”