Characteristics of Hydration Damage and Its Influence on Permeability of Lamellar Shale Oil Reservoirs in Ordos Basin

Figure 8

Microstructure of laminas and beddings after soaking. (a) Rock thin section after soaking in water. (b) Rock thin section after soaking in water-based drilling fluid. (c) The mineral on the rock surface fell off after soaking in water. (d) The pyrite coated with organic matter fell off after soaking in water. (e) Bentonite and solid particles in drilling fluid formed mud cake around pyrite. (f) The mud cake cracked after drying and dehydrating.

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