Assessment of Chemical Effects on Wellbore Stability in Transition Shale Formation

Table 6

Parameters used in the wellbore stability analysis considering the pore pressure and stress change due to the chemical effect.

Parameters	Values
Wellbore radius, (m)	0.1
Young’s modulus, (GPa)	15.0
Poisson’s ratio,	0.189
Undrained Poisson’s ratio,	0.31
Pore pressure, (MPa)	48.60
Maximum horizontal stress, (MPa)	73.80
Minimum horizontal stress, (MPa)	64.80
Vertical stress, (MPa)	81.36
Mud pressure, (MPa)	52.20
Pore solute concentration,	0.20
Mud solute concentration,	0.1
Swelling coefficient, (MPa)	2.0
Permeability coefficient, (m^2(PA·s))
Strata temperature, (°C)	12
Porosity,	0.1
Reflection coefficient,	0.2
Molar mass of solute (NaCl), (g/Mol)	58.5
Fluid bulk modulus, (GPa)	2.20
Solid bulk modulus, (GPa)	48.2
Solute diffusion coefficient, (m^2/s)
Rock matrix cohesion, (MPa)	8
Internal friction angle of rock matrix, (°)	35