Mechanical Properties and Failure Envelope of Kerogen Matrix by Molecular Dynamics Simulations
Tianhao Wu, Abbas Firoozabadi
Abstract
Shale gas has become a major source of gas supply in the United States and is becoming increasingly important worldwide. The key technique for the development is hydraulic fracturing in horizontal wells. Kerogen is the main component of organic matter in shale. It may be the spot of fracture initiation due to its weaker mechanical properties. The measurement of the mechanical properties and failure envelope of kerogen may be a challenge due to small-size kerogen aggregates immersed in shale rocks. In this work, we propose a practical scheme based on molecular dynamics simulations to estimate the elastic and relevant mechanical properties of kerogen for fracturing, including Young’s modulus, Poisson’s ratio, compressive and tensile strengths, as well as the parameters of the Mohr–Coulomb failure criterion. This work sets the stage to obtain basic kerogen parameters for the simulation of fracturing in shale rocks.