Landslides mudflow slump and creep are examples of

Landslides mudflow slump and creep are examples of   mass movement of soil due to gravity.

Explanation

When large mass of soil or rock falls downhill with Great speed due to gravity is called Landslides.Mudflow is a flow of huge amount of mud from the higher elevations during severe rains that washes down the loosened soil.Slump and creep are slow movement of soil particles and rocks to smaller distance and result due to water and gravity respectively.These all can be prevented by growing plants on erosion prone areas. Because,plant roots can prevent these type of erosion by binding the soil.

He should put sand around the spill in order to contain it so that it won't spread