A cliff collapse could affect the environment by exposing new rock (previously covered by the cliff) to the elements, which could result in runoff of a different nature when it rains. Additionally, the cliff would collapse upon whatever life/features existed at the base of the cliff. One of the most drastic effects could be the shaking of the earth. Cliff failures can result in earthquakes or, if the cliff collapses into a large body of water, massive tsunamis which radically impact coastal environments.