formation of a limestone pavement geography gcse
During periods of glaciation, glacial abrasion has scraped away the topsoil to expose the bare rock underneath. Limestone is a sedimentary rock that is made up of horizontal cracks called bedding planes and vertical cracks called joints.Limestone is made of Calcium Carbonate which is dissolved by rainfall which is a weak acid. This process is called chemical weathering.As a result of these features water is able to seep down through the cracks and into the rock making it seem to disappear. Therefore limestone is said to be a permeable rock.A limestone pavement is formed when rain water seeps through the joints and dissolves the limestone on each side making the joint wider.s the processes of dissolving limestone and cavern formation continue over time then caverns get larger and larger. Eventually there will be less rock supporting the roof of the cavern and it will collapse. This forms a very steep-sided valley called a gorge.