Logging prediction and evaluation of fracture toughness for the shales in the Longmaxi Formation, Southern Sichuan Basin

The mode-I fracture toughness is of great significance for evaluating the fracturing ability of shale reservoirs. In this study, the mode-I fracture toughness of the shale in the Lower Silurian Longmaxi Formation, Southern Sichuan Basin was determined with the Cracked Chevron Notched Brazilian Disc (CCNBD). Based on the experimental data, the relationships among the mode-I fracture toughness, the density, the acoustic time and the clay mineral...