| A | B |
|---|
| aquifer | rock or soil through which groundwater moves easily |
| artesian well | a well in which the water naturally rises above the level of the water table |
| bed load | sediment that is carried by a stream along the bottom of its channel |
| capacity | the total amount of sediment a stream is able to transport |
| cavern | a naturally formed underground chamber or series of chambers most commonly produced by solution activity in limestone |
| delta | an accumulation of sediment formed where a stream enters a lake or an ocean |
| discharge | the quantity of water in a stream that passes a given point in a period of time |
| divide | an imaginary line that separates the drainage of two streams; often found along a ridge |
| drainage basin | the land area that contributes water to a stream |
| flood | occurs when the discharge of a stream becomes so great that it exceeds the carrying capacity of its channel and overflows its banks |
| floodplain | the flat, low-lying portion of a stream valley subject to periodic flooding |
| geyser | a hot spring or fountain that ejects water at various intervals |
| gradient | the slope of a stream over a certain distance |
| groundwater | water underground in the zone of saturation |
| infiltration | the movement of surface water into rock or soil through cracks and pore spaces |
| karst topography | an area that has a land surface or topography with numerous depressions called sinkholes |
| meander | a looplike bend in the course of a stream |
| natural levee | an elevated landform that parallels a stream and acts to confine its waters, except during floodstage |
| permeability | a measure of a material’s ability to transmit fluids |
| porosity | the volume of open spaces in rock or soil |
| sinkhole | a depression produced in a region where soluble rock has been removed by groundwater |
| spring | a flow of groundwater that emerges naturally at the ground surface |
| stream channel | the course that the water in a stream follows |
| travertine | a form of limestone that is deposited by hot springs or as a cave deposit |
| tributary | a stream that empties itself into another stream |
| water cycle | the constant movement of water among the oceans, the atmosphere, geosphere, and the biosphere |
| water table | the upper level of the saturated zone of groundwater |
| well | an opening bored into the zone of saturation |
| zone of saturation | zone where all open spaces in sediment and rock are completely filled with water |
| rejuvination | a change in the base level of a stream, often caused by regional uplift |
| stalactite | an icicle-like structure that hangs from the ceiling of a cavern |
| stalagmite | a columnlike form that grows upward from the floor of a cavern |
