High brittleness is the prerequisite for the creation of a hydraulic fracture network, which is
crucial for shale reservoir development. The test evaluation methods are restricted in the
field by lack of continuous brittleness profiles. Mineralogical evaluation cannot incorporate
the external factors like stress state. The most widely used method is mechanical evaluation
method based on statistical results of Young's modulus and Poisson's ratio. This method
cannot explain the brittle tensile failure mechanism of shale and contradiction between high …