weathering

Limestone is a grey organic sedimentary rock made of calcium carbonate. A lime stone pavement is a large flat area of bare limestone from which soil cover has been removed over a long a period of time the acidic rainwater passes through soil it picks up humic acid from the rotting vegetation in the soil and becomes more acidicis. Rainwater picks up carbon dioxide as it passes through the atmosphere. As it passes through soil, the water picks up more carbon dioxide from organic debris. The water and carbon dioxide combine to form a weak carbonic acid. This acid reacts with minerals in the rocks and either dissolves them or turns them into other minerals. Rocks such as chalk and limestone contain calcium carbonate. The calcium carbonate reacts with the weak carbonic acid to form calcium bicarbonate which is soluble. It is then removed in solution. Carbonation is extremely effective at weathering limestone landscapes because limestone has lines of weakness in its bedding planes and joints. Carbonation has produced very distinctive landscapes, with distinctive landforms both on and beneath the surface. Limestone landscapes in Ireland include the Burren region of Co. Clare
Freeze-thaw
Freeze-thaw or frost shattering is the most common form of physical weathering. It is most effective in cold or upland areas of the world where temperatures move above and below freezing point (0°C), creating a frost cycle. Freeze-thaw is most effective on rocks that have joints, fractures and pore spaces.Water fills the spaces in the rock during the day, when temperatures are warmer. The water freezes if the night-time temperatures drop below freezing point. As the water turns to ice, its volume expands by about 9%. This applies pressure to the rock, and forces the space to open up. When the water melts during the day, the pressure is released.This sequence of freeze followed by thaw slowly widens the fractures and causes particles of rock to break off. These particles are angular in