Brittle minerals, mechanical properties and fracability evaluation of shales

The brittleness of shales is critical to hydraulic fracturing since rock with high brittle minerals are more likely to fracture and maintain open fractures. Shale rocks have a wide range of constituting components, and different minerals display distinct elastic behavior. The microscale measurements of mechanical properties indicate that pyrite has the highest Young's modulus, followed by quartz and feldspar. Organic matter was commonly recognized as the soft component, and has very low Young's modulus. Alkaline minerals show similar Young's modulus values to quartz and feldspar, and can be grouped into brittle minerals. The relative content, source and structure of brittle minerals can affect rock brittleness from multiple scales. Understanding the relationship between mineral compositions and geomechanical properties is beneficial for fracability estimation in engineering applications for shales. Document Type: Perspective Cited as: Xu, S., Wen, J., Liu, K., Shi, X., Dong, T. Brittle minerals, mechanical properties and fracability evaluation of shales. Advances in Geo-Energy Research, 2024, 14(1): 8-11. https://doi.org/10.46690/ager.2024.10.03