Analysis of Wellbore Stability considering the Interaction between Fluid and Shale

Table 1

Conventional evaluation on the wellbore stability of reservoir shale.

Evaluation indicator	Results
Content of the illite/smectite mixed-layer mineral	14%, 10% (%S)
Zeta potential	-8 ~ -4 mV
Cation exchange capacity	<10 mmol/100 g
Specific surface area	14~23 m^2/g
Roller recovery	>98%
Slope of capillary suction-time curve	0.0645
Linear expansion ratio	8-12%