Term
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Definition
| the study of the interrelationships of geologic materials and processes with water, espcially groundwater |
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Term
| water supply of the world |
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Definition
oceans=97.2
land areas=2.8
ice caps and glaciers=2.14
groundwater=0.61
soil moisture=0.005
freshwater lakes=0.009
rivers=0.0001 |
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Term
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Definition
-more than 98% of the available fresh water is groundwater
-only 0.001% of the total water supply is in the atmosphere
-the circulation of water from the sea to the atmosphere to the land and hence back to the sea |
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Term
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Definition
-zone of aeration
-the zone between the land surface and the water table |
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Term
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Definition
| the process by which plants give off water vapor through their leaves |
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Term
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Definition
| lateral movement of water in the vadose zone during and immediately after a precipitation event |
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Term
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Definition
| the part of the vadose zone that lies just above the water table, where water can be drawn upward by capillary forces |
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Term
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Definition
| the zone in which the voids in the rock or soil are filled with water at a pressure greater than atmosphere |
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Term
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Definition
| the surface in an unconfined aquifer or confining bed at which the pore water pressure is atmospheric |
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Term
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Definition
| the water in a stream that comes from effluent groundwater |
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Term
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Definition
| the total amount of water flowing in a stream |
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Term
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Definition
an open system in which solar radiation serves as a source of constant energy
-the energy of a river is due to the work done by solar energy, evaporating water from the ocean surface and lifting it to higher elevations |
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Term
| formation of precipitation |
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Definition
| since the atmosphere becomes less dense with altitude, a rising air mass must expand owing to the lower pressure |
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Term
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Definition
-a line drawn on a map, all points along which recieve equal amounts of precipitation
-in drawing the isohyets, such factors as known influence of topography on precipitation can be taken into account |
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Term
| events during precipitation |
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Definition
-the overland flow process occurs only when the precipitation rate exceeds the infiltration capacity
-in areas where soils have a high infiltration capacity this process may occur only during intense storms or when the soil is saturated or frozen |
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Term
| events during precipitation |
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Definition
-if the unsaturated zone is uniformly permeable, most of the infiltrated water percolates more or less vertically
-should layers of soil with a lower vertical hydraulic conductivity occur beneath the surface, then infiltrated water may move horizontally in the unsaturated zone |
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Term
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Definition
-interflow maybe substantial in some drainage basins and contribute significantly to total runoff
-thin,permeable soil overlying fractured bedrock of low permeability would provide a geologic condition contributing to significant interflow |
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Term
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Definition
| the lateral movement of water in an unsaturated zone during and immediately after a precipatation event |
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Term
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Definition
| a type of overland flow that occurs when throughflow reaches the land surface and drains across the land surface before reaching a stream |
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Term
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Definition
| the flow of water over a land surface due to direct precipitation |
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Term
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Definition
-a graph that shows some property of ground water or surface water as a function of time
-while the total runoff shown on the hydrograph gives no indication of its origin, it is possible to breakdown the hydrograph into its components of overland,baseflow, interflow, and direct precip |
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Term
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Definition
-the declining rate of recharge of a stream fed by only baseflow for an extended period
-the hydrograph of a stream during a period with no excess precipitation will decay, following an exponential curve |
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Term
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Definition
-function of the overall topography, drainage pattern, soils, and watershed geology
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Term
| baseflow recession example |
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Definition
-bucket with a hole near bottom
-as water drains from bucket the water level falls and the stream of water draining from the bucket declines in volume
-the stream of water draining will not increase until the water in the bucket is replinished |
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