The human activities directly or indirectly affect the nature. The deforestation and the removal of the vegetation for the purpose of development or timber, the land is exposed to the dangers of the landslide. The tress, plants and other vegetation keeps the soil in place with the help of their roots. The soil erosion is prevented by the trees, but the cutting down of them by the humans increases erosion and hence, the risk of landslide.
Sedimentary rocks are formed from pre-existing rocks or pieces of once-living organisms. They form from deposits that accumulate on the Earth's surface.