Research Article

NMR Experimental Study on Dynamic Process of Pore Structure and Damage Mechanism of Sandstones with Different Grain Sizes under Acid Erosion

Figure 9

Variation in the porosity of sandstones with soaking time: (a) Fine-grained; (b) medium-grained; and (c) coarse-grained sandstone.
(a)
(b)
(c)