Statistical grid nanoindentation analysis to estimate macro-mechanical properties of the Bakken Shale

Mechanical and Heterogeneous Properties of Coal and Rock Quantified and Mapped at the Microscale

“…It can be seen that different locations possess different micromechanical parameters. Even though some researchers thought these differences are due to the heterogeneous nature which originates from various phases that exist in coal and rock [51,59], this research showed that the microstructures of samples also play an important role to determine the differences of the maps of micromechanical parameters, which are avoided as possible in this study. It's worth noting that the distributions of different micromechanical parameters for one sample are very similar.…”

In-situ synchrotron characterisation of fracture initiation and propagation in shales during indentation

“…Cosenza et al, 2019). Also, the discrepancy between the macromechanical modulus from micro-indentation was only less than 15% in Bakken Shale which has (300μm) 2 representative elementary area (REA) (Liu et al, 2018), which demonstrates the representativity of micro-indentation is acceptable. The samples used in the in-situ experiments are around 3 × 3× 3 mm 3 , which is over 10 times greater than the REVs and can cover two or more laminae.…”

Applications of Diamond to Improve Tribological Performance in the Oil and Gas Industry

“…They found that the shale rocks exhibited considerable variation in terms of their mechanical properties, with the highest hardness and elastic modulus values recorded on the samples having the highest quartz content. Hardness values of between 1.32 and 3.08 GPa were recorded on shale specimens, although those figures masked some considerably higher hardness values in some regions of the specimens [34]. As well as having more clay minerals, the samples having the lowest hardness and elastic modulus also contained more pores and fractures than the other specimens.…”

“…During the drilling process, the drill bit may pass through greatly varying geologies, which may be reflected in their different properties. Even within a single rock type, the properties can vary markedly, as shown by various workers who used techniques such as nanoindentation and atomic force microscopy (AFM) to map the variation in properties of a wide range of rocks [27][28][29][30][31][32][33][34][35][36][37][38][39]. In granite, which is often used in laboratory-based trials of PDC cutters (see below), Heinrichs et al [35] showed wide variations in hardness of the three major constituents: quartz (H = 13 ± 1.0 GPa), feldspar (H = 10 ± 1.0 GPa), and biotite (H = 3.4 ± 1.3 GPa).…”