Located in a large area spanning the British Columbia and Alberta border, the Montney shale formation is one of the largest economically feasible resource plays in North America. Hydraulic Fracturing is one of the stimulation methods to enhance the gas production in which fractures induced by hydraulic loading are created. Initiation and propagation of hydraulically induced fracture is controlled by in-situ stresses magnitude and orientation and the reservoir tensile strength. If the in-situ stresses composing one vertical and two horizontal stresses are comparable or lie within a narrow range, the tensile strength becomes one of the most important parameters in governing hydraulic fracturing of the reservoir. This paper develops different point and line load tests to determine the tensile strength of Montney shale cores in two perpendicular directions. Test results indicate that Montney shale exhibits a high anisotropy in tensile strength. The tensile strength in the horizontal direction is dominated by the bond strength of the intact structure whereas that in the vertical direction is controlled by the existence of the natural beddings (foliations). This paper also addresses how this anisotropy in tensile strength could affect the pattern of hydraulically induced fractures in the field.

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