Geo Test 3

Water that flows on the surface is called ground flow.

False, Surface runoff: water that flows (runs off on) the ground surface. Also called overland flow.

The lowering of the water table around a well is called the drawdown zone.

False, The resultant lowering of the water table around the well is called a cone of depression.

T/F The zone where the pores between grains are completely filled with water is called the nonaeration zone.

False, The saturation zone is an area where the pores between grains are completely filled with water. The saturation zone stores water in countless pores and voids, like a hard sponge made of sand, gravel, and rock.

When discussing fluvial processes, the term "stream" refers only to very small channels.

False, The term "stream" is used for water flowing in channels, regardless of the channel size, whether a large river or small creek.

During the 1800s, when cotton was being farmed all over the Piedmont, soil was stabilized by sophisticated farming techniques, and very little soil erosion occurred.

False, This is because during the 1800s and early 1900's, stream aggradation (sediments building up in the stream, causing them to be braided and sluggish) was common because cotton farming caused huge amounts of soil erosion. During the winter, the cotton fields were bare, and soil was eroded off the cotton fields and delivered into the streams.

Water that percolates downward when pore spaces are filled beyond what capillary action can hold is called gravitational water

True

When streams are cutting down vertically, they are incising; this is known as stream incision.

True

When there is a lot of sediment being delivered to a stream, the stream's energy goes into trying to carry the sediment.

True

When there is not a lot of sediment in the stream, more of the stream's energy goes towards incision and widening the stream banks

True

Which is TRUE? Urban streams are usually aggrading because of all the dirt they receive. Urban areas have many impervious surfaces In rural areas, streams receive rainwater much more quickly than they do in urban areas.

Urban areas have many impervious surfaces

The terms drainage basin, watershed and catchment are interchangeable.

True

Fast water...

holds more sediment, slows down drops sediment

The upper limit of the water that collects in the zone of saturation is the water table.

True

Ultimate base level is sea level

True

The stream experiences Peak Flow when the amount of precipitation coming down is peaking.

False, Peak flow - the highest flow the stream experiences after the precipitation event - depends upon when the most water from the contributing tributaries arrives at the portion of the stream being measured.

When did Niagara Falls form?

12,000 years ago

How many feet back are the falls moving upstream per year?

4 feet

Which is FALSE? The mouth of the river occurs where it reaches base level. The numerous stream channels that occur in deltas are called distributaries Arc-shaped deltas are called arcuate deltas A many-lobed delta formed by changes in the location of the river mouth over time is called a lobular delta. Deltas form because the river increases in speed when it reaches the ocean, picking up more sediment.

A many-lobed delta formed by changes in the location of the river mouth over time is called a lobular delta. Deltas form because the river increases in speed when it reaches the ocean, picking up more sediment.

Which is true? Sinuosity is the ratio of the amount of void spaces between particles to the total volume of material Flat materials are more porous than rounded ones Tightly compacted materials are more porous A rock layer with cementing materials that dissolve easily will be more porous.

A rock layer with cementing materials that dissolve easily will be more porous.

Three common landforms (other than stream channels) that occur in deserts are:

Alluvial fans Bajadas Playas

Which is FALSE? Tablelands often occur in areas of sedimentary rock, where there is a capstone of resistant rock Areas of mesas, buttes and plateaus are often called tablelands Mass wasting plays an important role in forming tablelands Stream incision often plays a role in forming tablelands As buttes shrink, they form mesas

As buttes shrink, they form mesas

Percolation is when water soaks into the soil

False, Percolation: further permeation of water through pore spaces in soil, regolith, and rock

Streams that flow all year, fed by snowmelt, rainfall, and/or groundwater are "permanent streams".

False, Perennial streams flow all year, fed by snowmelt, rainfall, and/or groundwater.

The recharge area is the ground surface where water enters an aquifer, supplying more water, that is "recharging" it..

True

Which are not defined correctly? Capacity is a stream's ability to move particles of a specific size. Competence is the total possible load that a stream can transport. Suspended load is the dissolved load of a stream Solution load is fine-grained particles that are held aloft in the stream. Bedload is the coarser materials that are dragged, rolled or pushed along.

Capacity is a stream's ability to move particles of a specific size.(Capacity is the total possible load that a stream can transport.) Competence is the total possible load that a stream can transport.(Competence is a stream's ability to move particles of a specific size. It depends upon the stream velocity and the amount of energy the stream has available to suspend materials.) Suspended load is the dissolved load of a stream(Suspended load is fine-grained particles that are held aloft in the stream. The finest particles are not deposited until the stream velocity slows nearly to zero. Turbulence in the water, with random upward motion, is an important mechanical factor in holding a load of sediment in suspension.) Solution load is fine-grained particles that are held aloft in the stream.(Suspended load is fine-grained particles that are held aloft in the stream.)

Silts and sands occur at the highest point in a bahada or alluvial fan

False

Q = wdv. In this formula, w stands for weight, d for direction, and v for vector.

False To make this true: Q=discharge; w=width; d=depth; v=velocity

A small stream moving down a mountain slope will have greater velocity than a large river in flatter terrain, such as the Mississippi.

False, (This can seem somewhat counterintuitive, because often a small stream that is rippling along in a mountainous area will appear to be moving more slowly than a large, calm-looking river like the Mississippi. However, the current beneath the calm surface of the large river is strong.)

All of the land that is drained by a stream and its tributaries is called a Fluvial Zone.

False, A drainage basin is all of the land that is drained by a stream and its tributaries. They are also called watersheds or catchments

A graph of stream discharge over time for a specific location is called a Flow Chart

False, A hydrograph is a graph of stream discharge over time for a specific location (stretch of a stream).

hydrograph shows the stream discharges for all of the tributaries in a watershed.

False, A hydrograph is a graph of stream discharge over time for a specific location (stretch of a stream).

A drainage basin can only contain one stream

False, A major drainage basin system is made up of many smaller drainage basins. Each of the component drainage basins gathers and delivers its runoff and sediment to a large basin, concentrating the volume into the main stream. Each contributing tributary (a smaller stream that feeds into a larger one and has its own smaller drainage basin) contributes its water, pollution and sediment to the larger river.

A seepage area has a higher water flow than a spring.

False, A seepage area has lower water flow than a spring.

Sediments are sorted on alluvial fans by size because the winds blowing out of the canyon, along with gravity, cause them to travel different distances according to their size.

False, Alluvial fans are created because flowing water abruptly _loses speed when it leaves a constricted channel of a canyon and comes out into the open area of a valley. When the water loses speed, it cannot carry as much sediment, so it deposits layer upon layer of sediment along the base of the mountain block with each new precipitation event.

Most streams in the Georgia Piedmont are aggrading.

False, Streams are incising throughout the Georgia Piedmont. This is because during the 1800s and early 1900's, stream aggradation (sediments building up in the stream, causing them to be braided and sluggish) was common because cotton farming caused huge amounts of soil erosion. During the winter, the cotton fields were bare, and soil was eroded off the cotton fields and delivered into the streams. Many of the streams aggraded over 10 feet and at times over 20. All of the streams' energy went into trying to carry the sediment: there was no energy left to carve a stream channel.

The slope of the water table, which generally follows the contours of the land surface, controls groundwater movement.

True

Alluvial forms are caused by freeze-thaw processes breaking rocks into pieces

False, Alluvial fans are created because flowing water abruptly loses speed when it leaves a constricted channel of a canyon and comes out into the open area of a valley. When the water loses speed, it cannot carry as much sediment, so it deposits layer upon layer of sediment along the base of the mountain block with each new precipitation event. Over time, an alluvial fan is built. Materials that are deposited upon alluvial fans are sorted by size. Near the mouth of the canyon - at the top of the alluvial fans - the largest, heaviest (if any) are deposited first as the water starts to slow down as it emerges from the canyon. These materials grade down in size to pebbles and gravels as distance increases down the fan and the water slows down more. Then _sands and silts are deposited. Clays suspended in the water and dissolved salt are carried all the way to the valley floor to the playa (to be defined momentarily), where they precipitate out.

Fan-shaped sediment deposits that occur at the mouth of a canyon where an ephemeral stream channel exits into a valley are called arroyos.

False, Alluvial fans: fan-shaped sediment deposits that occur at the mouth of a canyon where an ephemeral stream channel exits into a valley.

Flooding never occurs in deserts because they are so dry.

False, Although precipitation events may be rare in a desert, when it does rain, the stream channels often fill up quickly to create torrential flash floods

The level below which a stream cannot erode is called the bottom level.

False, Base Level: the level below which a stream cannot erode its valley: it is the lowest point a stream can reach. The ultimate base level is sea level.

When it rains in the desert, the dry soils immediately soak up all of the moisture, and the rainwater deeply permeates the soils.

False, Because they are so arid (dry), vegetation is scattered in deserts, and much bare land is exposed. The ground is hard, and the soils are not very permeable. Thus, when it rains, the rainwater runs off the land instead of being absorbed into the ground.

The discharge of a stream never varies

False, Discharge at a particular site on the river changes from time to time, depending upon how much precipitation has occurred in the basin.

A stream's volume of flow per unit of time is called its velocity

False, Discharge is the stream's volume of flow per unit of time.

Drainage basins are separated from each other by what are called catchment ridges.

False, Drainage basins are separated from each other by divides, which are ridges that direct water on one side of the ridge to one stream, and direct water on the other side of the ridge to another stream. Continental Divides are extensive ridges and mountain areas that typically separate drainage basins that flow into different large bodies of water, such as the Atlantic Ocean or the Gulf of Mexico.

Streams that flow only after precipitation events and are not connected to groundwater are "occasional" streams.

False, Ephermeral streams flow only after precipitation events and are not connected to groundwater systems. Years may pass between flow events in these usually dry stream channels.

The combination of water loss from water and from plants is called transevaporation.

False, Evapotranspiration: this includes evaporation from soil water and surface water, as well as transpiration: the loss of water by plants.

The landform that is created when the neck of a meander is cutoff from the main channel is called a cut-off lake.

False, Eventually a high-flood event causes the stream to run straight across the neck, "cutting off" the meander, and deposition starts to seal off the meander. Eventually the former meander is completely isolated from the stream channel, and forms an oxbow lake

A type of perennial stream that have their headwaters in a wetter region, and the bulk of their course through arid regions is called a "semi-permanent" stream.

False, Exotic streams are a type of perennial stream that have their headwaters in a wetter region, and the bulk of their course through arid regions.

When general uplift occurs in a region, a streams meanders can become entrenched, forming what are called incision meanders

False, General uplift in a region can occur when isostasy causes land to rebound (for example, after glaciers have disappeared), or when a plate is lifted tectonically. In these cases, streams are is lifted higher above the ultimate base level, and incise into the uplifting portion of the lithosphere. Meanders become entrenched (deeper, like trenches), forming entrenched meanders

The surface lakes and streams, combined, are a much larger potential freshwater source than groundwater.

False, Groundwater is the largest potential freshwater source in the hydrologic cycle - larger than all surface lakes and streams combined. About half of the US population derives a portion of its freshwater from groundwater sources.

The science of water and its global circulation, distribution, and properties is called Fluvian.

False, Hydrology is the science of water and its global circulation, distribution and properties.

The most significant agent of erosion in deserts is wind.

False, In desert landscapes, running water is the most significant agent of erosion. Rivers and streams in deserts can be described by the type of flow, as follows

Infiltration is the further permeation of water through pore spaces in soil, regolith, and rock

False, Infiltration: water soaks into the soil

Streams that flow for several weeks or months each year and may have some groundwater inputs are called "desultory" streams

False, Intermittent streams flow for several weeks or months each year and may have some groundwater inputs.

Over time, when an oxbow lake fills with sediment, it is called a swale lake.

False, Over time, the oxbow lake fills in with sediment, and forms a "meander scar".

The highest flow a stream experiences after a precipitation even is called High Flow.

False, Peak flow - the highest flow the stream experiences after the precipitation event - depends upon when the most water from the contributing tributaries arrives at the portion of the stream being measured.

Transport of water vapor (and clouds, which are made up of liquid water droplets) from the ocean to land is through divection (horizontal movement)

False, Transport of water vapor (and clouds, which are made up of liquid water droplets) through advection (horizontal movement)

As water loses speed, it is able to carry more sediment

False, as it looses speed it carries less sediment.

The water level that is largely maintained by input from local groundwater is called Bottom Flow.

False, base flow

The water held within the pore space between soil particles is called void water.

False, capillary water: the water held within the pore space between soil particles

Alluvial fans form when water moves from an open area into a constricted one.

False, constricted to open

Q = wdv is the formula for the amount of bedload a stream is carrying.

False, the stream's discharge can be estimated by analyzing the width and depth of the channel and the speed (velocity) of its flow. The formula for that is Q = wdv.

The zone where the pores within soil and rock are not completed saturated is called the void zone.

False, the zone of aeration,

The loss of water by plants is called inspiration.

False, transpiration

A tributary is a stream that is in a different drainage basin.

False, tributary (a smaller stream that feeds into a larger one and has its own smaller drainage basin)

Extensive ridges and mountain areas that separate drainage basins that flow into different large bodies of waters, such as oceans, are called Great Divides.

False,Continental Divides are extensive ridges and mountain areas that typically separate drainage basins that flow into different large bodies of water, such as the Atlantic Ocean or the Gulf of Mexico.

Why are parts of California sinking up to a foot per year?

Groundwater Depression

Which is FALSE? A point where a steep drop occurs in the river channel is called a nickpoint. Nickpoints occur where softer rock occurs above harder rock As water flows over the nickpoint, the softer rock is eroded, causing undercutting. A pool of water at the base of a waterfall is called a plunge pool As undercutting and collapse of overhanging rock occurs over time, the waterfall retreats upstream. The process of erosion, where a stream lengthens at its headwaters in the opposite direction that it flows is known as headward erosion

Nickpoints occur where softer rock occurs above harder rock

Which is TRUE? Stream valleys tend to be U shaped in the upper reaches of streams Stream channels tend to be wide in the upper reaches of streams Stream channels have a gentle gradient in the upper reaches of streams The water is often muddy in the upper reaches of streams None of the above is true

None of the above is true

Which is TRUE? Confined and unconfined aquifers have similar water pressures A well drilled into a confined aquifer must always be pumped to make the water level rise above the water table. In a confined aquifer, the water is not under any pressure Water that is NOT under pressure is known as artesian water A well drilled into an unconfined aquifer never needs to be pumped. The pressure level to which artesian water can rise on its on is known as the volumetric surface. None of the above is true.

None of the above is true.

Matching Plateau Mesa Butte

Plateau A. an elevated region, typically with a fairly broad, flat top and steep sides Mesa B. broad, flat top and steep sides, roughly width is similar to height Butte C. Tableland landform that is much taller than it is wide

What is the difference between point and non-point source pollution?

Point source pollution comes from a single source, like an industrial pipe. Non point source pollution comes from surface run-off over a wide area, like a street or farm

Almost all of Georgia's rivers start in the state! Very unusual

Red

Which is mismatched? Sheetflow: overland flow Sheetflow: thin film of water running over the surface Rills: channels that are larger than gullies Rills: small-scale downhill grooves Gullies: larger than rills Streams: larger than gullies not tested on

Rills: channels that are larger than gullies

Which is true? Permeability is the ratio of the amount of void spaces between particles to the total volume of material Porous rocks are always very permeable Shale is often quite permeable Shale is never porous Sandstone can often be porous and permeable.

Sandstone can often be porous and permeable.

....is important to people in the coastal plain of Georgia.

The Floridan aquifer

The term for pumping water a well to the point that the water table is lowered is called drawdown.

True

Which is TRUE? Vertical erosion is much more important than lateral erosion in the lower reaches of a stream The sinuous, snake-like curves that occur in streams are called wavelets The strongest part of the stream current is called the laminar The outer side of a meander has a slower flow than the inner side The outer side of a meander is called the rip bank The inner side of a meander, where deposition of sand and gravel occurs, is called the point bar.

The inner side of a meander, where deposition of sand and gravel occurs, is called the point bar.

Which is FALSE? The decline in elevation from a stream's headwaters to its mouth is called the gradient. A stream's gradient generally forms a concave-shaped slope. The longitudinal profile of a stream is an aerial (overhead) view

The longitudinal profile of a stream is an aerial (overhead) view

Which is true? Floodplains are usually completely flat. The mounds and depressions seen on floodplains are known as ridge and swale topography When water flows over banks of a stream channel and deposits sands, the landform is called a natural levee. Usually larger particles, such as gravels, are deposited in the lowest-lying areas of floodplains.

The mounds and depressions seen on floodplains are known as ridge and swale topography When water flows over banks of a stream channel and deposits sands, the landform is called a natural levee.

Why is a karst aquifer more polluted than a sandy one?

There are large spaces in the dissolved limestone, so water and the pollutants in it can enter easily and travel far. Sand filters the water and makes it move more slowly.

A confined aquifer is bounded above and below by impermeable layers of rock or sediment.

True

After cotton farming declined, streams began to incise down through the alluvium that had built up in them, resulting in steep stream banks.

True

An aquiclude is a body of rock that does not conduct water in useable amounts.

True

An aquifer is a rock layer that is permeable to groundwater flow adequate for wells and springs.

True

An unconfined aquifer has a permeable layer on top and an impermeable one beneath.

True

As a drainage basin incorporates more and more smaller drainage basin, the volume of water, run-off and sediment grows greater, concentrating the volume into the main stream

True

Capillary action works through a combination of the cohesion of a liquid and the adhesion between the liquid and what is containing it.

True

For an unconfined aquifer, the recharge area generally extends above the entire aquifer; the water simply percolates down to the water table.

True

Groundwater is water beneath the surface, beyond the root soil moisture zone.

True

Groundwater mining is a condition that occurs when aquifers are pumped below their recharge capacities.

True

Groundwater tends to move toward areas of lower pressure and elevation.

True

In a confined aquifer, the recharge area is restricted, and recharge occurs in just a few limited places.

True

In the US today, in some places the water table has dropped more than 40 feet.

True

In the water cycle, precipitation can take the form of rain, snow, fog, etc.

True

Stream incision can occur when regional uplift is occurring in an area and after a period of aggradation ceases.

True

Streams with higher discharges will have wider and deeper channels, and the water in them will move with greater velocity.

True

The farther downstream one goes, the greater the volume of water a river carries. ***

True

When water slows down...

it loses heaviest sediments first

The Eastern Continental Divide runs through Georgia...

through Underground Atlanta!