Finally, the pore space of the permeable formations must not be so filled with swelling clays or mineral cements deposited by ground waters that the permeability will be reduced to the point that the oil cannot be pumped out of the formation.

• 最后，透水建造层的孔隙空间不能被由地下水沉积而形成的膨胀粘土或矿物胶结物所充填，否则其渗透性会减弱到不能将石油从含油建造中抽出来。