Geology Exam 2
Rank from smallest volume of freshwater to largest
rivers, swamps, lakes
Liquefation
saturated soil shaken in an earthquake
Ice ages
sea level higher because water was on land as ice masses
What does earths tilt cause
seasonal variation
Local water
shallow flow over short time and distance
steep, exposed slopes
snow and ice slide downhill and are not allowed to pile up
Distribution of karst across the world is equal to the distribution of
soluble rocks
What are signs that caves may exist below the surface?
-sinkholes -disappearing streams -limestone deposits
Slope failures
-undercut cliff -earthquake activity -too steep of slope -landslide -talus
More water
Pressure goes up
Water is attracted to what in the soil?
Quartz
Smaller pore = finer grain
More uplift in capillary rise
acid rain
Humans burning fossil fuels to release SO2 and NO2
soil layers
O, A, E, B, C, R
When groundwater gets contaminated the contamination moves along the direction of the groundwater. The contamination takes on a shape called
Plume
____ is the % of rock or sediment that consists of voids or openings and is a measure of a rocks ability to hold water
Porosity
What are the three properties that control the rate of groundwater flow through rocks
Porosity of the rock materials, steepness of water table, and permeability of the rock materials
Boundary between soil water and groundwater is divided by ____ pressure underground and ____ pressure above ground
Positive; negative
Angle of Repose
The maximum angle of a stable slope of a granular material determined by friction, cohesion, and the shapes of the soil particles. -angle of repose for material -amount of water -discontinuities: fractures, cleavage...
Sinkholes, disappearing streams, and limestone deposits can be indicators of ______ below the surface
caves
What settings is ground water found in?
caves, fractures, pore spaces
Percipitation
clouds cool and water molecules bond together, eventually falling towards earth
Bed temperature
cold based; frozen to bed, internal deformation, erosion is minial warm based;
Terracing
creating flat platforms in the hillside that provide a level planting surface, which reduces soil runoff from the slope.
Several processes are involved in generating rainfall or snow. First water is _______ from oceans and moved into the atmosphere. Next, the moisture condenses into clouds which cool and release rain and snow as _____
evaporated; precipitation
What area in the northern hemisphere was covered by ice 28000 years ago and still is today
greenland
Lakes and rivers are often found topographic lows where ____ is expressed as surface water
groundwater
Subsidence is the lowering of the elevation of the ground surface due to excessive pumping of:
groundwater
When will a cone of depression form?
groundwater is over pumped from an aquifer
common groundwater contaminants
hazardous chemicals and microbes
Water flows from areas of ______ pressure to areas with _____ pressure
high;low
Highest Volume to Lowest: Rank the reservoirs of freshwater by volume
ice caps groundwater lakes rivers
Wet-bottom glaciers
ice slips over meltwater/sediment slurry
When a continental ice sheet recedes sea levels ____
increase
removing vegetation
increases soil erosion -Lose stability roots give
the shape of the watertable
subtle expression of the land surface above it
Carlsbad Caverns in New Mexico were formed when limestone from a reef was dissolved by water rich in ______ acid. The acid migrated upward from hydrogen sulfide leaking from deeper accumulations of petroleum.
sulfuric
Lakes contain more freshwater than which of the following?
swamps
swelling clays
swells and compacts with water
contamination typically flows with thee groundwater down the slope of the water _____
table
temperate glaciers
temperature is at the pressure melting point throughout the entire ice body except for upper few meters of ice. Polar and Sub-Polar.
Rapid increases and decreases in global sea level are related to
the extent of continental ice sheets
Which WOULDNT be information collected by a hydrogeologist ?
the final intended use of groundwater
From highest to least rank the top four uses of freshwater in the U.S.
thermoelectric power, irrigation, public and domestic use, and industrial use
grooves and streaks
these are created as sediment trapped in the glacier is being carried by the flow
blue ice
this forms as snow gets buried and compressed
rock powder
this is created as glacial movement grinds up pieces of surrounding rock
Poor sorting has ____ porosity
lower
role of climate in weathering
warmer climates have more weathering
Chemical weathering occurs faster in what areas
warmer, humid areas than cold and dry
Glaciers float when they encounter ___
water
condensation
water molecules join together as they rise into the atmosphere and form clouds
Evaporation
water molecules rise into the atmosphere
Chemical Weathering involves:
water to dissolve rock and carry it away
More tilt of earth
more seasonality with more intense summers and winters
The majority of earths water is found in the
oceans
A spring is a place where water flows naturally from rock
onto land surface
_____ refers to the capacity of a rock to transmit a fluid
permeability
primary porosity
pore space
_____ is the most common type of rock to be dissolved and form caves
limestone
Water table:
Water follows the topography of land but flows down with gravity
Dissolution
can weather calcium carbonate in limestone to form caves along fractures or below water table
crevasses
fractures in a glacier, formed as internal stresses cause its upper surface to break
Part of a stream that receives water from the inflow of groundwater is called _____
gaining stream
Evidence of past glaciations
- glacial landscape features - glacial erratic (a rock that is out of place) -polished surface with glacial striations -isotopes
Characteristics of glaciers and glacial areas
- glaciers flow - glaciers form where snow and ice accumulate faster than they melt - glaciers may fracture forming crevasses
Which process of part of biotic weathering of a rock?
- root secretion -animal burrowing -root wedging
Life and time influences in weathering
-Biological weather of roots and animals -more time = more weathering - rocks with sharp, angular edges are not highly weathered
Features formed by glacier erosion
-cirques -aretes -U-shaped valley -hanging valler -Fjord -Moraines -Outwash Plain -Loess -permafrost
Conditions for glaciers
-cold climate -abundant snow; more snow falling than melting -snow must not be removed by wind or avalanches -must be above snow line
mass wasting
-creep -mudslide -submarine slopes -submarine debris flows -turbidity currents
The flow of material downhill will occur if:
-material is poorly attached to hillside -slope is steep -material is internally weak
Rates of weathering attack vary due to changes in
-mineral stability -degree of compaction or cementation -subtle differences in texture
what land areas were largely covered by a continuous ice sheet 28,000 years ago but are not likely covered by an ice sheet today?
-northern asia, canada, northern europe, northern united states
soil erosion
-overgrazing -erosion -removing vegetation -soil contamination -liquefaction -swelling clays -spoil compaction
How does vegetive cover benefit soil?
-protect from wind and rain -helps capture water -protection from runoff erosion
Soil
-referred to by geologists as regolith -layer of weathered unconsolidated material that contains organic matter that supports growth of plants
prevention of slope failure
-revegetation -engineered structures, retaining walls
Pleistocene Glaciation
20+ glaciations
What is karst topography?
A landscape full of depressions, weathered gray rock, and irregular drainage patterns through soluble rock
Which are human-made or human-induced substances that can contaminate water?
Agricultural wastes, human wastes & insecticides
____ is the name used for any type of rock that retards the flow of water in an aquifer
Aquifer
Why is water attracted to a glass beaker?
Because glass is made of quartz
Groundwater is free water that exists beneath earths surface as a liquid rather than being chemically _____ in minerals
Bonded
Where does movement move fastest
Center and slowest at the edges
Which countries or regions have widespread Karst formations?
Central Asia Southeast Asia Europe
Sinkholes in ____ topography may be large collapsed holes or small and subtle pits in the landscape
Karst
Example of groundwater depletion.
Land subsidence, example: leaning tower of pisa
which of the following are common sources of groundwater combination?
Landfills, service stations, and factories
What geological settings could springs occur?
Limestone aquifers, faults, and unconformities
Quartz
Strong not easy to dissolve
Aquifers
Subterranean, porous, water-holding rocks that provide millions of wells with steady flows of water.
Permability
The ability of rock or sediment to let sediment to let fluids pass through its open spaces or pores. -Includes straight flow paths -How easily material transmit water or fluid -Pore interconnectedness
In the U.S. which of the following is the primary use of freshwater?
Thermoelectric power
Ocean is salty because
Water dissolves rock and carries dissolved cations to ocean water
Calcite
Weak and easy to dissolve
Grounding line of a glacier
Where glacier is on land and transitions into sea water, where sea level changes
The water table has:
a shape similar to that of the land surface lying above it
Talus
accumulation of material at bottom of slope
An _____ is a large body of permeable, saturated material through which groundwater can flow well enough to yield sufficient water to wells and springs
aquifer
The Ogallala aquifer is located
beneath an area extending from South Dakota to the panhandle of Texas
Plants contribute to chemical and physical weathering in a process called _____ weathering when roots pry open joints or release carbon dioxide during respiration
biotic
If groundwater is moved from an aquifer by over pumping a cone of ____ will occur
depression
Secondary Porosity
develops later -fracturing -faulting -dissolution
Groundwaters are stationary with no movement or flow (T/F)
false
Groundwater
flows with local, intermediate, or regional flow
Ground water found in crystalline rock such as granite usually moves through _______ instead of pore spaces
fractures
Most groundwater is found in these three settings: pore spaces, subterranean caves & _______
fractures
Which of the following are common resources of groundwater contamination?
landfills, service stations, and factories
what are caves called that have been formed in regions with volcanic activity
lava tubes
which are natural substances that can contaminate groundwater?
lead and arsenic from mineralized rocks and sulfur
two common ways in which groundwater originates and accumulates
precipitation seeping into surface from where it accumulates & snowmelt seeping into surface where it accumulates
Infiltration
precipitation seeps into ground surface
Groundwater _____ is the term that describes the replenishment of groundwater either naturally or by human processes
recharge