Rivers Flashcards
Condensation
Gas turning liquid
Transpiration
Water evaporating from vegetation
Evaporation
Liquid water turning to gas
Throughflow
Movement of water thru unsaturated ground
Groundwater flow
Movement of water thru saturated ground
Surface runoff
Water moving across surface
Interception
Object stops precipitation reaching ground beneath
Percolation
Water travels from unsaturated to saturated ground
Infiltration
Water travels from surface into ground
Drainage basin
Area of land drained
Catchment area
Area within drainage basin
Watershed
Edge of high land surrounding drainage basin, marks boundary between drainage basins
Source
Start of river
Confluence
Where 2 rivers or streams meet
Tributary
Stream joining larger river or stream
Mouth
End of river, usually sea
As we move downstream what increases
Discharge, occupied channel width, channel depth, average velocity, load quantity
As we move downstream what decreases
Load particle size, channel bed roughness, slope gradient
Hydraulic action erosion
Force of river on banks makes air trapped in cracks, pressure weakens and wears away banks
Abrasion erosion
Rocks carried by river wear down banks
Attrition erosion
Rocks carried by river hit each other and become smaller and smoother
Solution or corrosion, erosion
Soluble particles dissolved into river
Suspension
Fine sediment carried by river making it look muddy
Traction
Larger pebbles and cobbles rolled along sea bed
Solution (not erosion)
Dissolved material carried in solution so can’t see
Saltation
Small pebbles moved when one pebble hits another making it bounce, chain reaction
Pothole
Upper course, Rocks called grinders swept in small depressions and abrade, river water swirled irregularly making vertical eddies, continues enlarging pothole
Waterfall
Upper course, Abrasion of soft rock, plunge pool made and waterfall made, hard rock undercuts and falls, repeating retreats waterfall, rocks fall in plunge pool
Meanders
Where pools (deeper) and riffles (shallow), fast water in pools erode, slow water in riffle deposits, bend created, fast water moves to outside bend due to momentum and erodes, deposition from outside of bend to inside of next, when floods water cuts across neck, deposition in neck of ox-bow cuts it off
Flood plain
Lower course, area river floods when exceed bank full discharge
Alluvium
Lower course, mineral rich load deposited in flood plain
Levee
Lower course, ridge of sediment deposited by river along banks by floods, larger sediment stays close to river so levee made
Arcuate deltas
Land around rivermouth arches into sea and river splits many times creating fan effect; made by strong currents, lots of sediment, strong waves push it back making smooth beach, Nile
Cuspate deltas
Just out like arrow into sea; made by river flowing into sea and crashing w/ waves so evenly spread sediment, Ebro
Birds foot delta
River splits on ways to sea and each parts just out to sea like birds foot; made by sediment rich rivers but less waves, Mississippi
Distributaries
Branch of river that doesn’t return to main
Flocculation
Process by which solute comes out of solution like clay joining to make large clumps
Causes of floods
More rain, impermeable rocks and soils, steeper land, deforestation, more road and building surfaces( buildings stop water and rivers redirect it), frozen ground or baked hard ground
Flashy and fatter profile
Enhance floods and oppose floods
Opportunities of living near river
Irrigation, household use, fishing, transport, tourism, building on flat land
