rivers and groundwater

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Earth as a System: The Hydrological Cycle

• illustrates the circulation of earths water supply

• most water is in the oceans and is continuously recycled through processes such as evaporation, precipitation, and infiltration.

Water’s Path: What Processes are involved in the water cycle?

PEIRTR!

• Precipitation

• Evaporation

• Infiltration

• Runoff

• Transpiration

• Respiration

What is Evaporation?

Evaporation is water going from liquid to gas

What is CONDENSATION?

Condensation is gas that goes back to liquid

what is Precipitation?

Precipitation is water in any form returning to Earth’s surface

EX: Rain, Snow, etc.

what is Runoff?

Runoff is water flowing beneath Earth’s Surface

What is Transpiration?

Transpiration is water coming from plants

What is Respiration?

Respiration is water coming from animals

What is Simplified Water Cycle?

numbers that are in cubic kilometers

Running Water: The amount of water that remains on the surface as runoff depends on what?

• Intensity and Duration of rainfall

• Amount of water already in the soil

• Nature of the surface materal

• Slope of the land

• Extent and type of vegetation

Running Water: What are Drainage Basins?

Drainage Basins are area of land drained by a stream

Running Water: what does ‘Divide’ do?

Divide separates drainage Basins

Smaller streams contribute to…

Larger Stream

What River is the most dangerous?

Santa Anna!

• has a huge drainage basins

What are Drainage Patterns?

• Networks of streams form distinctive patterns

• Drainage patters varies by terrain

What are the four common Drainage Patterns?

• Dendritic

• Rectangular

• Radial

• Trellis

What is Dendritic Pattern?

a treelike, branching network found in nature, where smaller tributaries join to form larger streams (drainage), or where structures branch out, resembling tree limbs or human veins.

• Dendritic Patterns develops on relatively uniforms surface materials

• looks like a tree with branches!

What is Radial Pattern?

Radial Patterns on isolated volcanic cones or domes

• Looks like a flower and in the middle its the volcano

What is Rectangular Pattern?

Rectangular Pattern develops on highlt jointed bedrock

• Looks very blocky!

What is Trellis Pattern?

Trellis patterns develop in areas of alternating weak and resistant bed-rock

• looks blocky but has more lines across

Streamflow Characteristics: Streamflow Factors that determine velocity

• Gradient or Slope

• Channel Characteristics: shape, size, roughness

Streamflow Characteristics: What is Discharge

Volume of water flowing in the stream (generally expresses as cubic feet per second)

The work of running water: What is Erosion?

Erosion is the warrying away- removal of rock

• the natural process where soil, rock, or land is gradually worn away and transported by agents like water, wind, or ice

The work of running water: What is Transportation?

Transportation is Transported Materials called Stream Loads

What are the three Stream loads?

• Dissolved load

• Suspended load

• Bed load

*STUDY: 9.12 Transport of Sediment

Work of Running water: Load is related to a streams….

• Competence and Capacity

• competence: maximum particle size

• Capacity: maximum load

Salt equals….

TDS!

• Total Dissolved solids in water!

Capacity is related to….

Discharge!

Colorado River

Super steep, it has HIGH COMPETENCE (it can move big material). Also LOW CAPACITY.

Mississippi

LOW COMPETENCE (muddy and no boulders), and HIGH CAPACITY

Work of running water: Deposition

• Deposition is caused by a decrease in velocity

• Competence is reduced

• Sediment begins to drop out

• a geological process where flowing water, having lost energy, drops transported sediment (sand, pebbles, soil)

Work of running water: Stream Sediments

• Stream Sediments are known as alluvium

• Well-sorted deposits

• materials (sand, silt, clay, gravel) deposited by running water

Name the Stream Channels

• Bedrock Channels

• Alluvial Channels

• Meandering Streams

• Braided Streams

Bedrock Channels

Bedrock Channels cut into the strata (strata: parallel layers of sedimentary rock or soil deposited by natural forces)

Alluvial Channels

Alluvial Channels are loosely consolidated sediment

• a natural watercourse with a bed and banks composed of loose, erodible sediment (alluvium) transported by the stream itself

Meandering Streams

Meandering Streams move in sweep bends at a slow graduing pace

• a single, sinuous channel that winds in snake-like curves

Braided Streams

Braided Streams are complex network of channels

Where does Deposition happen?

Any place it can!

• deposition: the geological process where flowing water, losing kinetic energy, stops transporting sediment and drops materials like pebbles, sand, and mud, forming features like deltas and floodplains

Shaping stream valleys: Base Level

Base Level is the lowest point a stream can erode to

• There are two General Types…

• Ultimate: sea level

• Temporary or local

Change in stream causes….

Readjustment of the stream - deposition or erosion

Rivers want to…..

flatten the earth

Shaping Stream Valleys: Valley Deepening

• V-shaped

• Downcutting base level

• incised meanders

• As land rises it can form incised meanders

Valley Deepning features

• Rapids

• Waterfalls

What river is a V shaped valley

Yellowstone

Shaping stream valleys: Valley Widening

Valley Widening are meandering streams

• Stream is near base level

• Downward erosion is less dominant

• Stream energy is directed side to side

• Shifting stream produces a broad flat valley floor of alluvium: floodplain

Meandering Streams

a single, sinuous channel that winds across4,5,6 flat terrain, characterized by high-velocity water eroding the outer banks (cut banks) and slow-velocity water depositing sediment on inner banks (point bars)

If land begins to uplift…..

incised meanders appear

Shaping Stream Valleys: Changing baseline can create….

• Incised Meanders

• Stream Meanders

Groundwater: Water beneath the surface

• Surface pore spaces are saturated with water

• Largest freshwater reservoir for humans

Geological Roles

• As an erosion agent, dissolving by groundwater produces

• sinkholes

• caverns

• an equalizer of streamflow

Distribution of water: Underground Zones

• Belt of Zones

• Zone of saturation

• all pore spaces in the material are filled with water

• water within the pores is groundwater

• water table

Water Table

the upper limit of the zone of saturation

Unsaturated zone is not…..

saturated water

Unsaturated

air inside

Saturated

water inside

Aquitard

• slow/stops the flow of water

• a geological formation with low permeability—such as clay, silt, or unfractured rock—that restricts groundwater movement

Storage of Movement of Groundwater: Distribution of groundwater

• Porosity

• Permeability

Porosity

• percentage of pore spaces

• Determines storage of groundwater

Permeability

• Ability to transmit water through connected pore spaces

• Aquitard

• Aquifier

Aquitard

an impermeable layer of material

• slows, stops water when passing through

Aquifer

a permeable layer of material

Wells, Artesian Systems, and Springs: Wells

• Pumping can cause a drawdown (lowering) of the water table

• Can form a cone depression

• Pumping can form a cone of depression in the water table

Wells, Artesian Systems, and Springs: Artesian wells

• water in the well rises higher in the initial groundwater level

• Must be confined to an aquitard

• Flows freely

Artesian systems have….

Recharge Areas

• water enters the groundwater system

Environmental Problem Related to Groundwater

• Land subsidence caused by its withdrawl

• Contamination