Unit 4
Which variables do Milankovic cycles take into account? a. depth and velocity of ocean currents b. EArth's orbit and tilt c. rates of Ice accumulation and ablation d. ocean salinity, depth, and current velocity
Earth'ss orbit and tilt
Today, continental glaciers are limited to: a. Greenland and Iceland b. Iceland and Antarctica c. Greenland and Antarctica d. Arctic ocean and GreenLand
Greenland and Antarctica
Vallleys carved by glaicers tend to be shaped like the letter _____ where as valleys carved by water tend to be shaped like the letter ____
U; V glaciers form fjords which are u shaped
The relatively flat part of the coena floor over which very deep water is found a. continental shelf b. continental rise c. MOR d. abysall plain
abyssal plain
Currently, almost all the glaciers on Earth are in a state of retreat, which means that the rate of ________ is less than the rate of ________. a. ablation; accumulation b. accumulation; ablation c. calving; advance d. formation; sublimation
accumulation; ablation when more accumulate -> advances when more ablation -> retreats
Which of the following is true about atmospheric CO2 concentration? a. Concentrations have been much higher at some times in the geological past b. the present rate of increase is unprecedented in the geological record c. is thought to help determine if Earth's climate is in a "greenhouse" or "icehouse" period d. all of the above
all of the above
overpumping of groundwater can lead to a. failure of nearby wells b. reversal of groundwater flow direction c. subsidence of the ground surface d. all of the above
all of the above
In order for a well to fuction properly it must be drilled below the water table into an: a. aquifer b. aquitard c. geyser d. spring
aquifer
The lowest elevation to which a stream can downcut is the _____. a. water table b. base level c. stream gradient d. floodplain
base level
Gently sloping deposits on coastlines that consist mostly of sands: a. tidal flats b. lagoons c. inlets d. beaches
beaches
the portionn ofo the sediment carried by a stream that is likely tro move the least between periods of flood: a. bed load b. dissollved load c. suspended load d. turbidity current
bed load - Larger particles roll, slide and bounce along < large> suspend load - fine particles (silt, clay) carried in flow dissolved load - ions from mineral weathering (dissolution)
the presence of crevasses indicates: a. the glacier is retreating b. brittle deformation near the glaicer surface c. plastic deformation of the glacial ice d. basal slip
brittle deformation near the glacier surface
Glacial ice exhibits ________ behavior near the top but ________ behavior beneath a depth of 60 m. a. plastic; brittle b. brittle; plastic c. plastic; elastic d. solid; liquid
brittle; plastic b >= 60m (has cracks) p < 60m
A terminal, or end moraine is formed: a. by deposition off fine, wind-blown rock flour transported by strong winds off the glacier b. from rock and soil pushed ahead of a glacier as it advanced c. where meltwter streams suddenly slowo at the toe of the glacier, depositing sediment d. by glacial sediment transported to the end(toe) of the glacier by the flow of the ice
by glacial sediment transported to the end(toe) of the glacier by the flow of the ice
In glcaically modified landscaes, straitifed sorted sand and gravel are deposited a. by meltwater in glacial outwash streams b. in lateral morains of moutians glaciers~ c. in terminal morains of continental glaciers d. by strong katabatic winds
by the meltwater in glacial outwash streams
If a material is porous, it a. is likely to be impermeable b. will also be permeable c. is considered to be an aquitard d. can be permeable or impermeable
can be permeable or impermeable
The ____ cycle helps us understand how the concentration of greenhouse gases changes in the atmosphere a. carbon b. rock c. hydrologic d. supercontinent
carbon - greenhouse
Whcih of hese is the longest-lasting sink for carbon dioxide a. biomass b. atmosphere c. carbonate rocks such as limestone d. bicarbonate ion in seawater
carbonate rocks such as limestone - carbon rocks
As a wave passes through the open ocean, the water molecules move a. horizontally b. straight up and down c. in a circular path d. in the direction of the wind
circular path
Which type of aquifer is least likely to be contaminated by pollution from the surface? a. perched aquifer b. unconfined aquifer c. confined aquifer d. all have the same risk
confined aquifer - confined p > uc > c
Braided streams ______ a. consists of a series of intertwined channels that are overloaded with sediment b. have flowing water either episodically or only during a portion of the year c. have a channel that is highly sinuous (curvy) d. are antecedent with respect to geologic structures
consists of a series of intertwined channeled that are overloaded with sediment
The broad, relatively shallow areass of the ocean addjacent to the continents are called: a. active margins b. continental shelf c. continental slope d. abysall plains
continental shelf shelf - 0 to 500m slope - 500 to 4km rise - 4km to 4.5km abysall - below 4.5
what variabels are considered when calculating the discharge of a stream a. velocity and depth b. width and depth c. cross-sectional area and length d. cross-sectional area and velocity
cross sectional area and velocity
This type of drainage network forms in areas with gentle slope and mostly uniform substrate a. trellis b. rectangular c. radial d. dendritic
dendritic - tree from substrate shallow slope radial - point uplift (mts.) rectangular - joint/fractures trellis - parallel to valley and ridges
Which aaprt of the sediment carried by a stream cosnist of ions dervived from weathering? a. bed load b. dissolved load c. suspend load d. runoff
dissolvedd load
Growht of continental glaciers has which of the following effects? a. uplift ofo the lithosphere by elastic rebound b. drop in sea level c. decrease of Earth's albedo d. All of the above
drop in sealevel
All the water in rivers and streams is derivewf directly ffrom rainfall runoff
false
Longshore currents _______ the shoreline a. not affected by b. flow directly towards c. flow parallel to d. flow directly away from
flow parallel to barrier islands
As a rule, ground water always flows from areas of a. higher water pressure to those of lower water pressure b. lower hydraulic head to those of greater hydraulic head c. greater hydraulic head to those ofo lower hydraulic head d. higher elevation to those of lower elevation
greater hydraulic head to those of lower hydraulic head
Because of wave refraction, erosion along an irregular coastline is___. a. greatest along headlands b. greatest in bayts c. even along the length of the coast d. the same as it would be along a smooth coastline
greatest along headlands - headlands = erosion bays = deposition
As more ice in the Arctic Ocean melts: a. heat absorption increases as the albedo icnreases b. heat absorption increases as the albedo decreases c. heat absorption decreases as the albedo decrease d. no effect on heat absorption
heat absorption increase as the albedo decrease - albedo = light absorption from ice
What type of water is most dense? a. high-salinity, cold water b. high-salinity, hot water c. low-salinity, warm water d. none, all water have the same density
high salinity and cold water -
The competence of a mountain river is _______ than that of a meandering river because: a. lower; the gradient is greater b. lower; there are more boulders c. higher; the gradient is greater d. higher; there is more water
higher; the graident is greater
The ____ cucle describes how water mvoes among reservoirs on Earth a. carbon b. supercontinent c. biogeochemical d. hydrologic
hydrologic - water
The stream gradient of most rivers a. is greater near the source than near the mouth b. is greater near the mouth than near the source c. does not change significantly as a river flows downstream d. is greatest for meandering sections of the river
is greater near the source than near the mouth gradient - slope/drop in elevation mouth is where it stops
Compared to interglacial periods, during ice ages eustatic sea level a. is higher because of subsidence of the crust from the weight of continental glcaiers b. is lower due to the much greater volume of sea ice c. is lower due to transfer of water from the coean to continetnal glaciers d. is higher because of the increased volume of MOR responsible for excess CO2
is lower due to transfer of water from ocean to continental glaciers
Karst landscape from predominately in what kind of rock a. limestone b. fractured granite c. sandstone d. shale
limestone
Rates of groundwater flow are ________ than stream flow because the water ________. a. lower; contains dissolved ions that slow it down b. lower; must make its way through tiny pore spaces c. higher; can flow over the surface of sediment grains d. higher; does not have streamed obstacles to overcome
lower; must make its way through tiny pore spaces
A well that pumps vast quantities of groundwater ___. a. lowers the local water table, forming a cone-shaped depression of the water table b. uniformly lowers the regional water table c. does not affect the water table as groundwater flow rates increase to compensate d. creates a cylindrically shaped unsaturated zone around the well
lowers the lcooal water table, forming a cone-shaped depression of the water table
What would Earth's climate be like today if there were no greenhouse gases in the atmosphere? a. about the same as now b. similar to that of the MEsozoic c. Much warmer than now d. much colder than now
much colder than now
The ratio of Oxygen isotopes in plankton fossils in deap sea sedinents can be used to determine a. the age of the fossils b. past carbon dioxide concentrations c. past temperatures d. seawater Ph
past temperatures
which of the following best decribes the glacial till? a. finely laminated layers of mud b. well-sorted sand c. a broad are of gravel and sandbars d. poorly sorted, unsolidcated sediment
poorly sorted, unsolidicated sediment
The total volume of open space between grains in a rock or sediment a. permeability b. porosity c. aquifer d. discharge
porosity
A type of rock that could be relatively impermable to ground water flow and serve as an aquitard a. shale b. fractured limestone c. well-sorted sandstone d. conglomerate
shale - seal rock sand stone and conglomerate are sediment
Which type of coastline would most likely contain estuaries or fjords? a. convergent b. divergent c. submergent d. emregent
submergent estuary - river flooded/submerged in seawater fjord - U-valley from glaciers
Unidirectioonal changes in Earth's history include all fo the following except: a. formation of continental crust b. oxygenation of the athmosphere c. supercontinent formation d. differentiation and formation fo the core
supercontinent formation
The ultimate base level of a stream can be no lower than a. the average elevation of the continent b. the average elevation of the ocean c. its flood plain d. the water table
the average elevation of the ocean - base level of water
Barrier islands are constantly moving in the direction of a. longshore current b. the tides c. downwelling current d. the prevailing winds
the long shore current
Period of cold climat with continental glaciations have occured at least five times siince the Archean
true
Ocean waves are created by _____ a. tides b. the moon c. the thermohaline circulation d. wind
wind