Experimental Study on the Self-Healing Behavior of Fractured Rocks Induced by Water-CO₂-Rock Interactions in the Shendong Coalfield

Figure 7

Microstructures of fracture-surface feldspars in the fine-grained sandrock specimen before and after the experiment and secondary sediments formed on the feldspar surfaces. (a) Albite crystals (before the experiment). (b) Corroded albite crystals (after the experiment). (c) Local zoom of the ellipse marking area in (b). (d) Secondary CaSO₄ crystals on the fracture surface. (e) EDS analysis in the No. 1 box of (d). (f) EDS analysis in the No. 2 box of (d).

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