Explanation: Landslides are simply defined as the mass movement of rock, debris or earth down a slope.

• They often take place in conjunction with earthquakes, floods and volcanoes. A prolonged spell of rainfall can cause heavy landslides that can block the flow of river for quite some time.
• The formation of river blocks can cause havoc to the settlements downstream on its bursting.
• In the hilly terrain landslides have been a major and widely spread natural disaster that often strike life and property and occupy a position of major concern.

Source: NCERT