Organic-rich shale in Lianggaoshan Formation: study on macroscopic and microscopic mechanical properties and mechanism of influencing factors

This study investigates the mechanical properties of organic-rich shale from the Lianggaoshan Formation using uniaxial and triaxial tests, nanoindentation, and atomic force microscopy. Key parameters such as elastic modulus and hardness are analyzed with NanoScope Analysis software. The results indicate that flat-laminated shale outperforms corrugated-laminated shale in terms of fracturing potential. As laminae increase, rock strength decreases, enhancing fracability, while thicker laminae hinder fracturing. The elastic modulus trend is clay minerals > calcite > quartz > pyrite, with Young’s modulus negatively correlated with mineral deformation.