| A | B |
|---|
| Runoff | Water that flows over the ground surface rather than soaking into the ground |
| Rills | A tiny groove in the soil made by flowing water |
| Gully | A large channel in soil formed by erosion. Only has water when it rains |
| Stream | A channel through which water is continually flowing downhill |
| River | A large stream |
| Tributary | A stream that flows into a larger stream |
| Drainage basin | The land area from which a river and its tributaries collect their water |
| Divide | A ridge of land that separates two drainage basins |
| Flood plain | A broad, flat valley through which a river flows |
| Meander | A looping curve formed in a river as it winds through its flood plain |
| Oxbow lake | The crescent shaped, cutoff body of water that remains after a river carves a new channel |
| Alluvial fan | A wide, sloping deposit of sediment formed where a stream leaves a mountain range |
| Delta | A landform made of sediment that is deposited where a river flows into an ocean or lake |
| Groundwater | Water that fills the cracks and pores in underground soil and rock layers |
| Stalactite | A calcite deposit that hangs from the roof of a cave |
| Stalagmite | A cone-shaped calcite deposit on the floor of a cave |
| Karst topography | A landscape in rainy regions with limestone near the surface. Sinkholes are common |
