There are three micromechanisms (steps) in pressure solution: dissolution under pressure, diffusion, and re-precipitation. The slowest of the three steps determines the rate of pressure solution. As deformation condition varies, the slowest step varies. At shallow burial depth where temperature and pressure are low, the kinetics of dissolution and precipitation are low, so the dissolution and precipitation steps are the controlling factors. On the contrary, at deep burial depth where temperature and pressure are high, the thin water film on the grain surface is not good media for transporting the dissolved materials, so diffusion becomes the controlling factor. Also, as noted in the macromechanical mechanisms, fracturing enhances the transport of the dissolved material away from the contact. Even though this also increases the dissolution rate, it is still the slowest, controlling the overall pressure solution.

There are several models proposed for the micromechanism of pressure solution (Renard et al, 1999). The 'water film diffusion' model assumes mineral dissolution takes place at the grain-grain contact area (Intergranular Pressure Solution, or IPS) with the solutes diffusing along an adsorbed water film layer. The precipitation of the solute occurs on the pore surface (Rutter, 1976). The driving force is the difference of normal stress between the grain contact and the pore. In this model, dissolution at the contact is stress-enhanced.

In the 'free-face pressure solution' model, dissolution occurs at the margins of the contacts, leading to undercutting and the eventual brittle or plastic deformation taking place within the contact (Tada et al, 1987). In this model, dissolution is strain-enhanced.

Raj and Chyung (1981) and Gratz and Bird (1993) proposed that the nominal contact between two grains is not smooth and flat and can contain channel and island structures at a nanometer scale or micron scale. Between the channels, plastic or brittle deformations can take place.