Stream And Sedimentary Rock Geology
This chapter covers Stream And Sedimentary Rock Geology.
You walk along a stream for 10 miles. At the beginning of your walk you were at 800 ft in elevation and by the end of you walk you were at 500 ft in elevation. What is the gradient of the stream?
30 ft/mile
In order of increasing grain size (smallest listed first) sedimentary grain sizes include:
clay, silt, sand, gravel
Which soil horizon is the zone of illuviation, where clays and dissolved minerals accumulate?
B
You measure the cross section of a stream, and find that the stream is 30ft wide and approximately 4 ft deep. After measuring velocity you find that the stream is flowing 2 ft/s. What is the discharge?
240 ft3/s
Which of the following statements best describes the process known as creep?
very slow, downslope movement of soil
The following are true of bauxite EXCEPT:
bauxite develops in the vertical soil series
Compacted mass of granular snow that is transitional between snow and glacial ice is called:
firn
Which of the following soil orders is found in Arkansas and develops on older land surfaces, causing the soil to be lower in nutrients?
ultisols
Alpine glaciation results in ______ glaciers, whereas continental glaciation results in _________.
valley, ice sheets
An aquifer that is 30ft thick and 2000ft wide has a hydraluic conductivity of 10 ft/day. Two wells were installed 1000 ft apart. The water level at Well #1 was 500 ft and the water level at well #2 was 300 ft. What is the discharge through the aquifer?
120,000 ft3/day
The Ozark Mountains of northwestern Arkansas are characterized by ________ sedimentary rocks, which result in a ________ drainage pattern.
flat-lying; dendritic
The Two drainage basins for Fayetteville, Arkansas are:
Illinois River and Beaver Reservoir
The Earth’s climate is affected by changes in the amount of incoming energy received from the sun. Over approximately 100,000 year cycles the relative shape of Earth’s orbit changes and this is called ________:
eccentricity
Which scenario does NOT increase stream velocity, but instead causes water flowing in a stream to slow down?
wide and shallow channel shape
You walk along a stream for 5 miles. At the beginning of your walk you were at 800 ft in elevation. By the end of the walk you were at 500 ft in elevation. What is the gradient of the stream?
60 ft/mile
What is the correct order from largest to smallest of Earth’s water reservoirs?
ocean, cyrosphere, groundwater, surface water
The subsurface zone in which the voids are not completely filled with water is called the:
-unsaturated zone
-vadose zone
which of the following rock types or sediments would NOT be a good aquifer?
granite
Which of the following will decrease the likelihood of mass wasting:
gentle or low slope
Which of the factors of soil formation is the most important for controlling the mineral content and texture of the soil?
parent mineral
If all soil horizons are present in a soil profile, what is the correct order of the horizons from top to bottom?
O, A, E, B, C
The following are true about mudflows EXCEPT:
dominantly coarse-grained material
The steepest angle at which a pile of unconsolidated grains remains stable is called:
angle of repose
The force that is parallel to a slop and acts to move soil or bedrock down the slope:
shear force
All of the following are true regarding advancing glaciers EXCEPT:
ablation is greater than snowfall accumulation
The Laurentide ice sheet covered much of the northern potion of North America during the Last Glacial Maximum approximately __________years ago.
18,000
The Mississippi River delta is an example of which type of delta?
stream-dominated
Which of the following is a potential source for groundwater contamination?
-leaky landfills
-oil pipelines
-storm water runoff from city streets
-ocean water
Which soil horizon is the zone of illuviation, where clays and dissolved minerals tend to accumulate?
B
Where recharge is less than evapotranspiration, the water will rise in an unconfined aquifer.
False
The Earth’s external heat engine is the driving force for the hydrologic cycle.
True
Continental glaciers do not exist on Earth today.
False
Solifuction is a type of mass wasteing often associated with permafrost.
True
The percentage of volume occupied by voids is called permeability and the capacity to transmit fluid through pores is called porosity.
False
During interglacial periods in Earth’s history, sea level will rise.
True
Groundwater always flows from low hydraulic head to high hydraulic head.
False
When a glacier retreats, the ice reverses direction and flows uphill against the force of gravity.
False
Velocity is greatest in a stream over the deepest part of the channel, just below the surface of the water.
True
A karst landscape can be found in northwestern Arkansas.
True
Steep-sided, bowl-shaped depression carved out by the head of a glacier.
cirque
Glacial material that is unsorted and unstratified
till
A steep-sided ride that separates adjacent glacially carved valleys
arete
Moraine marking the farthest advance of a glacier.
terminal
Glacial material that has been deposited by melt water.
Outwash
The typical shape of stream valleys in the headwaters of mountainous areas.
V shaped
The typical shape of glacial valleys due to erosion as the glacier moved down the valley
U shaped
Stream that receives water from the saturated zone.
gaining
Stream that is characterized by very sinuous, single channels that migrate over time.
meandering
Stream type often found in outwash plains and characterized by multiple channels due to a high sediment load.
braided
The two drainage basins for Fayetteville , Arkansas are:
Illinois River and Beaver Reservoir
Which of the following factors will increase the likelihood of mass wasting?
Bedrock (and panes of weakness in the bedrock) oriented parallel to slope
Alpine glaciation results in ______ glaciers, whereas continental glaciation results in ________.
valley; ice sheets
If all soil horizons are present in a soil profile, what is the correct order of the horizons (from bottom to top)?
C, B, E, A, O
In the hydrologic cycle, the process of ________ occurs when rain or snowmelt soaks into the ground.
infiltration
What is the correct order of events to generate sediment and form a sedimentary rock?
weathering, erosion, transportation, deposition, preservation, lithification
_________ is a type of mass wasting where unconsolidated material moves downslope very slowly.
Creep
Which of the following soil orders is found in eastern Arkansas and develops on alluvium, which causes the soil to be higher in plant nutrients.
alfisols
All of the following are true regarding retreating glaciers EXCEPT:
the ice reverses direction and flows uphill
Chemical sedimentary rocks from from…….
precipitation of ions from an aqueous solution
An aquifer is 20 ft thick and 4000 ft wide. It has a hydraulic conductivity of 12 ft/day. Two wells were installed 800 ft apart. The water level at Well 1 was 300 ft and the water level at well 2 was 200 ft. What is the discharge through the aquifer?
120,000 ft3/day
Which of the following Milankovitch cycles occurs on approximately 100,000 year cycles and refers to the change in the relative shape of the Earth’s orbit?
eccentricity
Which of the following processes take the greatest amount of energy, or requires the fastest flowing water?
erosion
How much of earths water exists in the oceans?
almost all of earth’s surface water exists in the oceans
Which soil horizon is the zone of eluviation, where clays and dissolved minerals are removed due to water leaching?
E
What size sediment can be transported by glaciers?
all sediment sizes can be transported by glaciers
When a large rock becomes dislodged and drops down a steep slope, this an example of a ________.
Fall
The Ozarks are characterized by _________ sedimentary rocks, which results in a ___________drainage pattern.
flat-lying; dendritic
Which of the following statements about lithification is FALSE?
involves the precipitation of cement around sediment grains
Which of the following types of weathering causes a chemical transformation to minerals and rocks?
hydrolysis
Which mineral is the most resistant to weathering at Earth’s surface?
quartz
You measure the cross section of a stream, and find that the stream is 50 ft wide and approximately 4 ft deep. After measuring velocity you find that the stream is flowing 2 ft/s. What is the discharge?
400 ft3/s
Valleys that have been carved by glaciers are typically _______ shaped.
U
When a layer of sandstone moves downslope along a layer of shale, this is an example of a ________.
slide
What type of sedimentary rocks were deposited in the shallow, coastal waters of the Gulf Coastal Plain in Arkansas?
Evaporites
Which acid forms naturally in rain water and dissolves limestone to form conduits and caves?
Carbonic
In rock or sediment, the percentage of volume occupied by voids is called _________ and the capacity to transmit fluid through pores is called ________.
porosity; permeability
Imagine a valley containing four stream terraces. Where would the oldest stream terrace be found?
the highest terrace (furthest from the stream)
All of the following are examples of mass wasting where the descending mass moves as a viscous fluid EXCEPT:
Rock avalanche
The most common chemical weathering product of feldspar is quartz.
False
The Mississippi Alluvial Valley is composed of layers of limestone, sandstone, and shale.
False
During interglacial periods , sea level will rise.
True
Mass wasting is possible only with the aid of a transportation agent such as water, wind, or ice.
False
When recharge is greater than evapotranspirtaon, the water table will rise in an unconfined aquifer.
True
The C horizon is very similar to the parent material for the soil profile.
True
A mountain is an example of a depositional environment.
False
Most groundwater exists as underground rivers.
False
Detrital bedrock that would form an aquifer
sandstone
Chemical sedimentary rock that can form karst landscape
limestone
example of an organic sedimentary rock
coal
detrital bedrock that would form an aquitard
Shale
Example of an evaporite sedimentary rock
rock gypsum
Subsurface zone in which the pores are filled with air and water
vadose
subsurface zone in which the pores are completely filled with water
phreatics
stream that receives water from saturated zone
gaining
stream that is characterized by very sinuous, single channels that migrate over time
meandering
stream type often found near glaciers and characterized by multiple channels
braided
Which type of chemical weathering is very efficient at weathering limestone?
Dissolution
The _______ horizon is very similar to the parent material.
C
Potassium feldspar chemically weathers to produce _______ in great quantities.
Kaolinite
Why do rainforest soils lack nutrients?
Rainforest soils are heavily leached
Rank the chemical weather speed of granite and basalt from slowest to fastest.
granite with very few or no cracks; granite with abundant cracks; basalt with few to no cracks, basalt with abundant vesicles
Chemical sedimentary rocks form from _______.
The precipitation of ions in a solution
Why is coal different from other sedimentary rocks?
It is made of almost entirely or organic matter
Which of the following is a likely explanation for why there is limestone near the summit of Mount Everest, the tallest mountain on Earth?
The limestone found at the top of Mt Everest was formed in an ocean
What are the chief constituents of detrital sedimentary rocks?
quartz and clay
A mass movement in which a cohesive block of earth or rock slips downhill relatively quickly in one piece along a zone of weakness is called a _______.
slide
Mass movements that move materials down a curved surface, creating scarps on a slope are known as a ______.
slump
When large rocks become dislodged and drop down a steep slope, the mass movement is called a ______.
fall
________ are very gradual mass movements in which the whole slope moves downhill slowly.
Creeps
When a slurry of unconsolidated material moves downhill it is called a _______.
flow
How much of Earth’s surface water exists in the oceans?
almost all of Earth’s surface water exits in the oceans?
Which ocean is the Earth’s largest?
the Pacific Ocean
Where is most of Earth’s freshwater found?
as ice at Earth’s surface
How does water get from the oceans onto land?
Ocean water evaporates to from gaseous water and moves into the atmosphere, where it condenses into liquid water and falls out of the atmosphere to land as rain
What would happen to the oceans if surface runoff and groundwater flow did NOT occur?
the oceans would become smaller
Depositional landforms are created where energy of the stream __________.
has decreased
When to stream terraces form?
when streams exist under alternating erosional and depositional conditions
What is a stream terrace?
a remnant of an older floodplain that sits above the stream valley
How many stream terraces can exist along a single valley?
Generally two, stream terraces will stop forming when deposition and valley forming begin
Are stream terraces depositional or erosional landforms?
stream terraces can either be depositional or erosional
Imagine a valley containing four stream terraces. Where would the youngest stream terrace be found?
the lowest terrace
How well pores are connected to allow groundwater to flow is known as ________.
permeability
What type of rock to caves most commonly form in?
limestone
Which is the best definition of glacial snow line?
the line dividing the zones of accumulation and melting of ice at the surface of a glacier
Under what conditions will the front of a glacier remain stationary?
glacial fronts remain stationary when melting and snow accumulation are equal
Which way does ice flow in a glacier retreating uphill?
downslope
How would a snow line on a glacier move as a glacial front is advancing?
the snow line would move downslope
How would you expect the front of a glacier to move if it undergoes a period of net accumulation, followed by net wastage, and finally a period of net accumulation?
The glaciers front would move forward, backward, then forward again.
What size sediment can transported by glaciers?
all sediment sizes can be transported by glaciers
Which of the following is a characteristic of glacial till?
the particles are often scratched and polished
What term to we use to describe variations in the shape of Earth’s orbit around the Sun?
eccentricity
When was the last glacial maximum in North America?
18,000 years ago
________ is when physical forces break down solid rock into smaller sediments.
mechanical
Which slope composition is the most stable?
solid bedrock
What is the term used to describe the hypothetical line the water in a confined aquifer would rise to if it weren’t trapped?
potentiometric surface
Which of the following components of soil is usually in the greatest percentage?
mineral portion
The majority of groundwater occurs as underground rivers.
False
Which rock type can contain fossils?
Sedimentary Rocks
What is a slide?
Mass movements in which there is a distinct plane of weakness between the slide material and underlying stable material
What is the term for sediment deposited by streams?
Alluvium
What type of sedimentary rock is Rock salt
chemical
What is bed load?
larger sediments that bounce, roll, or slide along the bottom
What chemical sedimentary rock is the most abundant?
limestone
How will the water table respond when there is a drought?
water table will fall
Which of the following is NOT an agent of erosion?
heat
In order for an aquifer to use useful for human consumption, what kind of porosity and permeability should it have?
high porosity, high permeability
In a series of stream terrace levels, the oldest terrace is the one that is the lowest in elevation.
False
What type of sedimentary rock is shale?
detrital
What type of glacier is an ice sheet
a large, massive glacier that moves independently of the topography
Stratified drift is deposited by ____________.
meltwater from the glacier
In the hydrologic cycle, the process of _________ occurs when plants pump liquid water to the atmosphere during photosynthesis.
transpiration
Continental glaciation…..
is characterized by large ice sheets
An aquifer is 50 ft thick and 8000 ft wide has a hydraulic conductivity of 2 ft/day. Two wells were installed 2,000 ft apart. The water level at Well 1 was 900 ft and the water level at well 2 was 850 ft. What is the discharge through the aquifer?
20,000 ft3/day
The subsurface zone in which the voids are not completely filled with water (includes air and water) is called the:
vadose zone