Earth Science Exam 5- Ground Water
Sinkhole
-A cavity in the ground, especially in limestone bedrock, cause by water to disappear underground -Depressions formed as underlying rock is dissolved by seeping water, or by cave roof collapses
Aquitard/Aquiclude
-A geological formation or stratum that significantly retards fluid movement -An impermeable geologic formation of stratum which will not hold or transmit fluid -Shales and many crystalline rocks act as boundaries for aquifers
Natural Levee
-An elevated landform that parallels some streams and acts to confine their waters, except during flood stage -Produced along the edges of stream channels by overbank deposits
Karst Topography
-Consist of numerous depressions 'sinkholes' -Regions characterized by caves, springs, sinkholes, and disappearing streams. -Karst Topography occurs in areas with large amounts of limestone in the subsurface; dissolution occurs as carbonic acid in ground reacts with calcite in limestone
Artesian Well
-Situation in which groundwater under pressure rises above the level of the aquifer -Natural or manmade wells where water gushes to the surface under pressure, confinement of tilted aquifer by impermeable beds
Zone of Aeration
-The zone where all open spaces in sediment and rock are completely filled with water -Contains mostly air in its pore spaces, some water adheres to particles here
Braided Stream
-Type of alluvial channel consisting of a broad network of diverging and converging channels -posses an intricate network for dividing and rejoining channels separated from one another by sand and gravel bars, supplying exceeds transport capacity
Stalagmites
A column like rock formation that grows upward from the flood of a cavern
Flood plain
A flat, low-lying portion of a stream valley. Heavy rains cause the stream to overflow its bank.
Stream Terrace
A flat-benchlike structure produced by a stream, which was left elevated as the steam cut downward
Geyser
A foundation of hot water ejected periodically
Permeability
A measure of a material's ability to transmit water The ability of materials such as rocks to transmit fluid
Fumarole
A vent of volcanic area from which fumes or gases escapes
Delta
An accumulation of sediment formed where a stream enters a lake or ocean -Fan shaped sedimentary structures produced as moving water flows into a standing body of water and drops sediments
Drainage Basin
An area drained by a river or stream and all its tributaries -Dendritic, Parallel, Trellis, Radical
Stalactite
An icicle-like structure that hangs fro the ceiling of a cavern
Depression
Area of land that is sinking
Turbulent Flow
Complex mixing occurs as water molecules move in all directions -**most water flow is turbulent
Cone of Depression
Cone-shaped depression in the water table immediately surrounding a well
Zone of Saturation
Contains mostly water in its pore spaces
Hydrothermal
Denoting the action of heating water in the earths crust
Fluvial Channel Flow
Downhill, flow confined to long trough-like depressions Rill>Brook>Creek>Stream>River
Suspended load
Fine sediment carried within the body of flowing water, clay and silt
Travertine
Form of limestone deposited by mineral springs
Point Bar
Inside of the stream, where sediments are dropped by slower moving waters
Incised Meander
Meandering channel that flows in a steep, narrow valley
Aquifer
Porous and permeable layers of rock that can hold and transmit groundwater
Dissolved load
Portion of the stream that is carried in solution
Oxbow Lake
Produced as meanders are cut-off by the main channel
Bed load
Sediment that is carried by a stream along the bottom of a channel, sand and gravel to boulders
Meandering Stream Braided Stream
Stream and River channels are characterized as ________________ or _____________
Cut Bank
The area on the outside of the meander, stream velocity
Gradient
The downhill flow of a stream; generally measured in the feet per mile (Rise over Run)
Base Level
The level below which a steam cannot erode, the lowest point to which they can erode
Infiltration
The movement of surface water into rock or soil through cracks and pore spaces
Discharge
The quality of water in the stream that passes a given point in ta period of time
Water table
The upper level of the saturated zone of groundwater
Porosity
The volume that represents the amount of water rocks can hold
Capillary fringe
Thin, irregular layer where groundwater moves upward into the zone of aeration due to surface tension
Divide
Topographical highs separating drainage basins
overbank deposites
an alluvial deposit consisting of sediment that has been deposited on the floodplain of a river that has broke overtop that banks; consisting of fine sand, silt and clay
stream load
carry solid matter as a result of erosion
Meandering stream
consist of a single sinuous channel with looping curves, known as meanders
Sheet Flow
downhill movement of slow shallow water moving over the surface. causes erosion as the water moves by the channel flow
Hydraulic action
erosion that occurs when the motion of water against a rock surface produces mechanical weathering
Subsidence
gradual caving in or sinking of an area of land
Laminar flow
lines of flow parallel to one another, no mixing of layers, flow primarily in one direction, rare
Saltwater Incursion
movement of saline water into aquifers which leads to contamination
Impermeable
not allowing liquid through
Stream piracy
phenomenon occurring when a stream drainage system diverted from its own bed and flows rather than going down the bed of a neighborhood stream
recharge
precess by which ground water is absorbed into the zone of saturation
Topography
representation on a map of the natural and the artificial features in an area
Disappearing streams
river that loses water as it flows downstream; infiltrates to the ground recharging local ground water; the water table is below the bottom of the stream channel
Alluvium, Alluvium deposits
sediments deposited by running water
Run-off
water that flows over land rather than infiltrating into the ground Controlled by the infiltration capacity, the ability of the surface to absorb water