vocablary

Flood when a thing is beyond its limit.

Delta is water. there all around the world. it looks like a fan

Sediment matter that settles to the bottom of a liquid; dregs.

Erosion the process of eroding or being eroded by wind, water, or other natural agents.

Weathering wear away or change the appearance or texture of (something) by long exposure to the atmosphere.

Drainage basin is a geographic term about rivers. It is also called catchment, catchment area, catchment basin, drainage area, river basin, and water basin. It is an area of land. All water that falls on that land flows into one river. ... A watershed is a line separating two drainage areas.