Fine-grained, water-wet ductile rocks will seal as long as the capillary pressure exerted on the seal (the difference between the water and the petroleum fluid pressure) is less than the capillary displacement pressure of the matrix [[porosity]] of the seal. Under these conditions, the relative [[permeability]] of the seal to petroleum is zero. The accumulation remains preserved until one of three things happens:
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Fine-grained, water-wet ductile rocks will seal as long as the capillary pressure exerted on the seal (the difference between the water and the petroleum fluid pressure) is less than the capillary displacement pressure of the matrix [[porosity]] of the seal. Under these conditions, the relative [[permeability]] of the seal to petroleum is zero. The [[accumulation]] remains preserved until one of three things happens: