Uniformity and volume-representativity of consecutive submillimetre wafers of shale for SANS and USANS investigations

Multiscale micro-architecture of pore space in rocks: size, shape, deformation and accessibility determined by small-angle neutron scattering (SANS)

“…Various approaches to sample preparation for SANS and USANS measurements include gently crushed coarse powders (sieved to a required grain size to represent an average of a larger rock volume) or solid samples cut in different orientations to bedding, e.g. [ 36 ]; chosen thicknesses of samples vary from 0.2 to 1 mm [ 37 ] to about 50 μm [ 21 ], depending on the microstructural aspect studied. The precedent (and not well examined) issue is spatial uniformity of rocks formed in similar depositional environments on the centimetre linear scale.…”

“…The precedent (and not well examined) issue is spatial uniformity of rocks formed in similar depositional environments on the centimetre linear scale. It has been recently studied for shale cores [ 37 ] as a fundamental question where several adjacent samples are used and the results are interpreted jointly (e.g., for destructive microstructural measurements using high uniaxial pressure [ 38 ] or a chemically reactive environment [ 39 ]).…”

The Influence of SC-CO2 on the Nanopore Structures of Different Types of Shales Based on Small-Angle Neutron Scattering and Multifractal Methods

“…Ji et al used SANS and USANS to examine the degree of nano to-micropore uniformity of a rock body on the submillimeter to centimeter scale. Their study presented a test of the hypothesis of volume representativity of pore structure information measured by SANS and USANS for shale wafers (0.22–1 mm) cut from six North American unconventional shale cores of different maturities (New Albany Shale and Marcellus Shale) . SANS can not only measure the pore structure parameters of connected pores but also obtain the structural parameters of unconnected pores .…”

“…Their study presented a test of the hypothesis of volume representativity of pore structure information measured by SANS and USANS for shale wafers (0.22−1 mm) cut from six North American unconventional shale cores of different maturities (New Albany Shale and Marcellus Shale). 35 SANS can not only measure the pore structure parameters of connected pores but also obtain the structural parameters of unconnected pores. 36 This information is critical for evaluating the degree of microcrack extension development in shale under long-term CO 2 -salt-geothermal-water interactions.…”