Study on Rock Mechanics Parameters of Chang 7 Shale in Longdong Area in Ordos Basin

Abstract

Rock samples from X-1 and X-2 well of Chang 7 shale in Longdong area in Ordos Basin are studied through triaxial compression test and acoustic wave test in order to obtain accurate data about the mechanical characteristics of the stratum and fracturing parameters.The static Young’s modulus ranges from 2.213 GPa to 4.195 GPa and the static Poisson’s ratio ranges from 0.181 to 0.239 in triaxial compression test. The dynamic Young’s modulus ranges from 2.659 GPa to 5.03 GPa and the dynamic Poisson’s ratio ranges from 0.20 to 0.29 in acoustic wave test. It can be seen that the dynamic Young’s modulus is slightly larger than the static Young’s modulus, and the relation between them is Es=0.8492Ed-0.1349, while the dynamic and static Poisson’s ratios are basically same, that is, μs≈μd.