how does the process of frost wedging contribute to the weathering of rock
Frost weathering The traditional explanation for frost weathering was volumetric expansion of freezing water. When water freezes to ice, its volume increases by nine percent. Under specific circumstances, this expansion is able to displace or fracture rock. At a temperature of -22 °C, ice growth is known to be able to generate pressures of up to 207MPa, more than enough to fracture any rock.[6][7] For frost weathering to occur by volumetric expansion, the rock must have almost no air that can be compressed to compensate for the expansion of ice, which means it has to be water-saturated and frozen quickly from all sides so that the water does not migrate away and the pressure is exerted on the rock.[6] These conditions are considered unusual,[6] restricting it to a process of importance within a few centimeters of a rock's surface and on larger existing water-filled joints in a process called ice wedging.
Deposition (geology) Cohesion of sediment occurs with the small grain sizes associated with silts and clays, or particles smaller than 4Ï• on the phi scale.[4] If these fine particles remain dispersed in the water column, Stokes law applies to the settling velocity of the individual grains,[4] although due to sea water being a strong electrolyte bonding agent, flocculation occurs where individual particles create an electrical bond adhering each other together to form flocs.[4] "The face of a clay platelet has a slight negative charge where the edge has a slight positive charge, when two platelets come into close proximity with each other the face of one particle and the edge of the other are electrostatically attracted."[4] Flocs then have a higher combined mass which leads to quicker deposition through a higher fall velocity, and deposition in a more shoreward direction than they would have as the individual fine grains of clay or silt.