Study on Wellbore Stability and Failure Regions of Shale considering the Anisotropy of Wellbore Seepage

Table 1

The horizontal ground stress was determined by field and laboratory experiments.

Parameters	Field hydraulic fracturing	Laboratory experiment	Average value
Maximum horizontal stress gradient (g/cm^3)	2.73	2.87	2.80
Minimum horizontal stress gradient (g/cm^3)	2.24	2.18	2.21