It is an important mechanical parameter for fracture toughness that affects hydraulic fracturing. Some
methods such as indoor test core and logging data interpretation are commonly used to obtain fracture
toughness. These methods, however, have their own limitations. Liu's method has focused the mechanical properties of shale including fracture toughness based on micro-/nano-indentation experiments. Zeng's method has pointed that the former method of calculating fracture toughness ignores the
maximum holding stage in the indentation-displacement curves, they point out and correct the fracture
stress intensity factor model, but the final calculation of the fracture toughness of the numerical difference is of two orders of magnitude. In this paper, micro-indentation experiments were carried out to
further analyze and correct the model by collecting and analyzing Longmaxi shale cuttings. After Zeng
and Liu's methods are combined, the irreversible elastic energy by energy area actually was measured. To
some extent, the difference between the two kinds of fracture toughness is reduced.