Mechanical-Chemical-Mineralogical Controls on Permeability Evolution of Shale Fractures

Figure 6

Aperture evolutions with time for various shale. (a) Fluid pH = 4.0, (b) fluid pH = 5.0, (c) fluid pH = 6.0, and (d) fluid pH = 7.0. For shale with different mineralogical composition, aperture evolution shows distinct trend. Higher acidic fluid increases the aperture for Longmaxi shale and Green River shale while lower acidic fluid close fractures for all three kinds of shale.

(a)

(b)

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