Preliminary results of air permeability test under tensile stress condition using a hollow cylindrical rock specimen

Features of CO2 fracturing deduced from acoustic emission and microscopy in laboratory experiments

“…Results of Brazilian tests with the discs oriented to make fracture along the rift plane on 33 cylindrical samples of the same kind of Kurokami‐jima granite, measuring 45 mm diameter and 30 mm length, showed an average tensile strength of 3.38 MPa with a standard deviation of 0.21 MPa [ Ishida et al, ]. Effective porosity of the granite was 0.84%, where the pore and the bulk volumes were measured with the saturation and the buoyancy methods, respectively [ International Society for Rock Mechanics, ], and its intrinsic permeability obtained by air permeability test for hollow cylinder samples was around 9 × 10 −19 m 2 [ Ishida et al, ]. The intrinsic permeability corresponds to 1 × 10 −11 m/s of hydraulic conductivity, which is within the extent from 10 −12 to 10 −8 m/s for general granitic rock shown by Vutukuri and Katsuyama [].…”