The Research on Borehole Stability in Depleted Reservoir and Caprock: Using the Geophysics Logging Data

Table 1

The value of proportional coefficient 𝐾.

Formation property	Boundary conditions
	No fault	Fault boundary
		Normal fault	Thrust fault
Isotropic formation	𝜈1−1−𝜈	(1) 2sin𝜙1+sin𝜙	1−𝜈(𝐾𝑝+1)
		(2) sin𝜙+1−2𝜈1+sin𝜙
Anisotropic formation	𝜈1−^′𝐸𝐸^′(1−𝜈)	(1) 2sin𝜙1+sin𝜙	1−𝐾𝑝𝜈𝜈−^′𝐸𝐸^′
		(2) 𝜈1−𝐾𝑝−𝜈^′𝐸𝐸^′