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Abstract Clay-rich shale rock reveals greater compressibility than tight sandstone. Experiments have been conducted on Liupanshan—Yabrai shale core samples to select appropriate correlations to represent permeability as a function of effective stress. Mineralogical，mechanical properties and microscopic pore structure were analyzed by rock dynamics mechanics experiments，X-ray diffraction analysis，field emission scanning electron microscope image analysis and high pressure mercury injection to investigate stress sensitivity mechanism of shale reservoir. The results show that the exponentiation curve fit the relationship of effective stress and permeability well；The core with high clay content，low Young?s modulus present relative high stress-sensitivity and larger stress-sensitivity coefficient；shale reservoirs with nanoslot pores and throats exhibit highly stress-sensitive because of the irreversible deformation of easy-compressed throats. An increase in mesopore permeability contribution is correlated with an increase in stress sensitivity.
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2015, Vol. 34 
