Cliffs are usually formed because of processes called erosion and weathering. Weathering happens when natural events, like wind or rain, break up pieces of rock. In coastal areas, strong winds and powerful waves break off soft or grainy rocks from hardier rocks. The harder rocks are left as cliffs.

Cliffs are usually formed by rock that is resistant to weathering and erosion. Sedimentary rocks most likely to form cliffs include sandstone, limestone, chalk, and dolomite. Igneous rocks such as granite and basalt also often form cliffs.

Wave pounding is the ‘sledge hammer’ effect of tonnes of water crashing against cliffs. It shakes and weakens the rocks leaving them open to attack from hydraulic action and abrasion. Eroded material gets carried away by the wave.

Hard Engineering – Cliff Drainage

Erosion is the geological process in which earthen materials are worn away and transported by natural forces such as wind or water. Most erosion is performed by liquid water, wind, or ice (usually in the form of a glacier). If the wind is dusty, or water or glacial ice is muddy, erosion is taking place.

Grazing. If too many animals graze the same land area, the animals’ hooves pull plants out by their roots. A land is overgrazed if too many animals are living there. Grazing animals can cause erosion if they are allowed to overgraze and remove too much or all of the vegetation in a pasture.

Animals Cause Erosion and Weathering Some animals weather rocks by scraping them as they feed. Other animals change Earth’s surface by burrowing into it and moving material. Too many animals in one place can destroy most of the plants, leading to faster erosion.