Relationship between Amorphous Components and Mechanical Properties in Shale Using X-ray Diffraction: A Case Study from the Permian Wujiaping Formation Shale Reservoir, Sichuan Basin

HIGHLIGHTS (1) The amorphous inorganic and organic components in the shale reservoir of Well DY1H in the Permian Wujiaping Formation in eastern Sichuan exhibit brittle and plastic characteristics, respectively. (2) The precision of calculating the brittleness index through the mineral composition method is influenced by variations in the content of amorphous organic components within shale reservoirs. (3) The relationship between the content of amorphous inorganic components in shale and the proportion of mixed layers of illite and montmorillonite is evident, as it can be used to determine the plastic characteristics of the shale.