This thesis reports an experimental investigation into intergranular pressure solution (IPS) as a compaction mechanism in wet (i.e. brine-saturated) halite aggregates and wet quartz sands. The aims were to determine the compaction behaviour under conditions favouring IPS, to clarify the underlying microscale processes, and to test the applicability of microphysically-based models describing the rate of compaction and deformation of polycrystalline aggregates by IPS. Halite and quartz were studied for the following reasons. Halite is an attractive material to study IPS in the laboratory because of its high solubility and rapid dissolution/precipitation kinetics in water. In the fields of radioactive waste disposal, salt mining and sa...