Term
| What is the earth's most critical resource? |
|
Definition
|
|
Term
| What percentage of the earth's water is readily available for use by humans? |
|
Definition
|
|
Term
| Where is the most of earth's water located? |
|
Definition
oceans & lakes (97.41%)
ice & snow (1.984%) |
|
|
Term
| Where is readily available freshwater located? |
|
Definition
ground water (.592%)
surface water: rivers & lakes (.0071%) |
|
|
Term
| In what ways could population growth be limited by low water supply? |
|
Definition
| Limited water will cause population growth to stop either through drought & famine or through laws. |
|
|
Term
| Describe the hydrolic cycle. |
|
Definition
| Rain falls to the ground and either sinks in to become groundwater or runs off into rivers and lakes. Water is evaporated from surface water (rivers/lakes) into clouds and falls again as rain. |
|
|
Term
| What is perhaps the most over-exploited of Earth's resources? |
|
Definition
|
|
Term
| What is instream river use? Name 2 examples. |
|
Definition
| Using river water in a way that does not take the water from the river; navigation, hydropower |
|
|
Term
| What is offstream river use? |
|
Definition
| Extracting water from rivers. |
|
|
Term
| How does consumptive offstream river use differ from non-comsumptive use? |
|
Definition
| In consumptive use (ex.irrigation), the water is not returned immediately to the source, which means that ppl will eventually be forced to import water or mine for groundwater. Nonconsumptive use (ex. domestic water) is returned relatively quickly, but it may be polluted or unusable. |
|
|
Term
Name the type of lake according to this balance:
precipitation + runoff = evaporation + outflow |
|
Definition
|
|
Term
Name the type of lake according to this balance:
precipitation + runoff = evaporation (w/ no outflow) |
|
Definition
|
|
Term
Name the type of lake according to this balance:
precipitation + runoff < evaporation (w/ or w/o outflow) |
|
Definition
|
|
Term
| What is an example (mentioned in class)of how easily humans can destroy the delicate balance of a lake? Who is responsible for this? How lond did it take for the lake to dry up? |
|
Definition
*the Aral Sea
*Soviets
*only about 30 yrs |
|
|
Term
| Where does40% of the public water supply in the U.S. come from? |
|
Definition
|
|
Term
| Name 3 cities for which groundwater is the only source of water. |
|
Definition
| Miami, Memphis, Tucson, Honolulu |
|
|
Term
| Name three areas in the U.S. whose only source of agricultural water is groundwater. |
|
Definition
| Arizona, California, and the Midwest |
|
|
Term
|
Definition
| the fraction of volume that is void spaces in the ground (how much space there is between grains/rocks in the ground) |
|
|
Term
|
Definition
|
|
Term
| What are the names for the zones above and beneath a water table? |
|
Definition
*above: zone of aeration
*beneath: zone of saturation |
|
|
Term
| In which zone would you find an aquifer (or groundwater)? |
|
Definition
|
|
Term
| Water sinking into the ground is called ___? |
|
Definition
|
|
Term
| What is a perched water table called? |
|
Definition
|
|
Term
|
Definition
| water-saturated rock with enough porosity and permeability to allow water to be extracted |
|
|
Term
| How are unconfined aquifers connected to the surface? |
|
Definition
|
|
Term
| How are unconfined aquifers recharged? |
|
Definition
| recharged locally by rain |
|
|
Term
| Is recharge in a confined aquifer instantaneous? |
|
Definition
| nopers, it's local, but it takes a while |
|
|
Term
| What is a cone of depression? |
|
Definition
| change in aquifer's water level due to pumping the water out faster than permeability allows movement[image] |
|
|
Term
|
Definition
| the difference between regular water level and the level of water in a cone of depression |
|
|
Term
| What are things that draw-down is affected by/depends on? |
|
Definition
| amount of renewal, amount & span of use; permeability of aquifer, rate & time of extraction |
|
|
Term
| How do unconfined aquifers interact with rivers? |
|
Definition
| they can cause either losing stream or gaining stream |
|
|
Term
|
Definition
| river in which water infiltrates into groundwater |
|
|
Term
|
Definition
| groundwater flows up into a river |
|
|
Term
| What do we call the area wher aquifers intersect the surface of the ground? |
|
Definition
|
|
Term
| What is a confined aquifer? |
|
Definition
| groundwater under pressure that is trapped by aquicludes |
|
|
Term
| What is another name for a confined aquifer, and why are these very valuable resources? |
|
Definition
*artesian well
*flows naturally out of the ground b/c of a hydrostatic head, so you don't have to waste energy pumping |
|
|
Term
| What are critical issues of groundwater management and conservation? |
|
Definition
| groundwater mining, interaction w/ saltwater, and groundwater quality |
|
|
Term
| What is the sustained yeild of an aquifer? |
|
Definition
| the amount of water that can be withdrawn constantly and over a long period of time |
|
|
Term
| If the rate of extraction of water from a well exceeds the sustained yeild, the resultin overdraft is known as ____? |
|
Definition
|
|
Term
| What is the name of the aquifer that sustains agriculture in the High Plains? |
|
Definition
|
|
Term
| Why is groundwater mining a particularly serious problem? |
|
Definition
| because much of the groundwater is fossil water acquired during the glacial age |
|
|
Term
| What is ground subsidence? |
|
Definition
| problem that occurs when so much groundwater is removed that the ground sinks significantly |
|
|
Term
| Why does saltwater intrusion of aquifers occur? |
|
Definition
| If too much water is pumped from an aquifer near an ocean, seawater will invade and destroy the source of freshwater. |
|
|
Term
| Is saltwater more or less dense than freshwater? |
|
Definition
| saltwater is more dense, that's why in coastal aquifers, freshwater floats on seawater |
|
|
Term
| Where is saltwater intrusion most likely going to be a problem? |
|
Definition
| places with dense populations near the coast, like Miami and the eastern seabord |
|
|
Term
| What results from the interaction between Earth's internal and external processes? |
|
Definition
|
|
Term
| How do internal processes build? |
|
Definition
| they convert Earth's heat energy into potential/mechanical energy |
|
|
Term
| How do external processes degrade? |
|
Definition
| they liberate potential energy by erosion and mass wasting |
|
|
Term
| What are some factors that determine landforms? |
|
Definition
| local geology (e.g. types of rocks, plate tectonic setting), climated, time, glaciation |
|
|
Term
| What are present-day landforms heavily influenced by? |
|
Definition
| Pleistocene glaciation, either directly (ice-carved landforms) or indirectly (sea-level change, wetter climate then than now) |
|
|
Term
| What are the four types of landforms and erosional agents? |
|
Definition
| rivers, coasts, glaciers, deserts |
|
|
Term
| In river systems, what is the function of the hydrolic cycle? |
|
Definition
| conversion of Solar energy to mechanical energy |
|
|
Term
|
Definition
| erosion by rivers/streams/running water |
|
|
Term
| The ability of a river to erode and the size of the particles that it can transport are determined by _____? |
|
Definition
|
|
Term
| Does the size of the particles a river can carry increase of decrease with its velocity? |
|
Definition
|
|
Term
| What is the velocity of a river determined by? |
|
Definition
|
|
Term
| What determines the sediment load that a river can transport? |
|
Definition
|
|
Term
| What is discharge in terms of a river? |
|
Definition
| the volume of water that goes through a point in a certain amount of time - velocity (x) cross section |
|
|
Term
| What determines the gradient of a stream or river? |
|
Definition
| elevation of the headwaters, base level (in most cases, sea level), location within the drainage basin |
|
|
Term
| What are the characteristics of youthful fluvial topography? |
|
Definition
| broad uplands and steep-walled canyons completely filled by fast-flowing rivers, no flood plains; the river mainly erodes |
|
|
Term
| What are the characteristics of mature fluvial topography? |
|
Definition
| wide valleys only partly filled by the river, noticeable but narrow flood plans; the river erodes and deposits sediment |
|
|
Term
| What are the characteristics of old age fluvial topography? |
|
Definition
| no uplands, flood plains many km wide; river mainly deposits sediments |
|
|
Term
| What are flood plains and how have they been used since the Neolithic period? |
|
Definition
| flat and wide expanses of fertile soil, used for agriculture |
|
|
Term
| Why are flood plains so fertile and therefore heavily populated? |
|
Definition
| They are subject to periodic flooding that deposits rich sediments. |
|
|
Term
| How do rivers build their flood plains? |
|
Definition
| By eroding the outer margins, or cut banks, of the meanders and depositing point bars on the inner margins.
[image] |
|
|
Term
|
Definition
| a feature of mature flood plains formed by cutoff of meanders; water in an oxbow lake is usually clearer than the river and contains a unique ecosystem
[image] |
|
|
Term
|
Definition
| the intensity of rainfall/snowfall increases the river discharge to the point that it overflows its banks |
|
|
Term
| Where do flash floods occur? |
|
Definition
| places witout a flood palin; level of water increases and decreases quickly |
|
|
Term
| What type of flood takes many days to accumulate, occurs in a wide flood plain, and may take months to recede? |
|
Definition
|
|
Term
| How frequent are catasrophic floods? |
|
Definition
| they aren't very frequent, but still inevitable |
|
|
Term
| What are recurrence intervals? |
|
Definition
| statistical averages in which the inverse of the probability that a flood of a given size will occure on any given year; every year there is a 1% probability that there will be a 100 year flood |
|
|
Term
| Why is correctly estimating the probability of very large floods difficult? |
|
Definition
| insufficient data,and the effects of climate change and climate cycles |
|
|
Term
| How does urbanization of flood plains increase the flooding potential? |
|
Definition
| it replaces permeable soil w/ impermiable surfaces like concrete, so the water cannot sink into groundwater |
|
|
Term
| What are some methods of flood mitigation currently in use, even though none are good for the long-term? |
|
Definition
| artificially filling above the 100 yr flood level; building artificial levees; building flood control damns |
|
|
Term
| The Pacific coast is an active continental margin, and the Atlantic coast is a passive continental margin. Which coastline is submergent and which is emergent? |
|
Definition
*Pacific is emergent
*Atlantic is submergent |
|
|
Term
Where do waves acquire their energy?
What factors determine wave size? |
|
Definition
*from the wind
*wind velocity, duration of wind, and fetch |
|
|
Term
|
Definition
| distance over which wind blows |
|
|
Term
| In what type of waves does energy move forward, but mass does not? |
|
Definition
|
|
Term
| In what type of waves does energy and mass move forward? |
|
Definition
|
|
Term
| Wavelength ______ as waveheight _______. |
|
Definition
| Wavelength DECREASES as waveheight INCREASES. |
|
|
Term
| Name the four types of waves of oscillation. |
|
Definition
| ripples, chop, fully-developed seas, and swell |
|
|
Term
| What is the lowpoint of the chop called? |
|
Definition
|
|
Term
| What is another word for waves of translation? The foremost of these waves that hits the shore is called a ____? |
|
Definition
|
|
Term
| What is one way in which waves erode the shore that is actually a mini-explosion? |
|
Definition
| compression and expansion of air in cracks of rocks |
|
|
Term
| When does the most erosive action of waves take place, and what is it characterized by? |
|
Definition
| during storms; battering-ram action of "tools" (e.g. rocks, driftwood, houses, tourists) picked up by the sea |
|
|
Term
| How do waves straighten irregular coastlines? |
|
Definition
| wave energy is focused toward headlands and away from embankments, which is called wave reflection |
|
|
Term
| What are longshore currents? |
|
Definition
| "rivers" of seawater forced to move parallel to the shore when waves approach at an angle |
|
|
Term
|
Definition
| sediment transported by longshore currents that is constanly modifying beaches |
|
|
Term
|
Definition
| structures built to preserve beaches, but only serve to aggravate the problem further down the coast |
|
|
Term
|
Definition
| Rip currents form where longshore currents overflow the surf zone (like a river overflowing its banks). They move sediment (& people) toward the open ocean. |
|
|
Term
| What are sand beaches and where are they usually found? |
|
Definition
| shorelines dominated by sand deposition; supplied by rivers and wave erosion; distinctive of submergent coasts |
|
|
Term
| What are some features of depositional coastlines? |
|
Definition
| barrier islands, spits, baymouth bars. tidal marshes |
|
|
Term
|
Definition
| redistribution of sediment during large storms |
|
|
Term
| What type of erosion are cliffs and wave-cut platforms dominated by, and which type of coast are they distinctive of? |
|
Definition
| shorelines dominated by wave erosion; more distinctive of emergent coasts |
|
|
Term
| What are wave-cut platforms and cliffs? |
|
Definition
| erosion by waves carves flat surfaces backed by vertical walls
[image] |
|
|
Term
|
Definition
| an old wave-cut platform cut off from the coast
[image] |
|
|
Term
|
Definition
| [image]
"has more of a slope instead of being sheer like the cliffs, with little or no wave-cut platform" |
|
|
Term
|
Definition
| a partially enclosed basin in which river water mixes with sea water; usually a river valley near the mouth invaded by the sea (submerged by sea-level rise at the end of the Pleistocene glaciation) |
|
|
Term
| What is a Bird's Foot Delta? |
|
Definition
| delta with relatively little redistribution of fluvial sediments by coastal processes; an example is the Mississippi
[image] |
|
|
Term
| What is an arc-shaped delta? |
|
Definition
| delta where the redistribution of fluvial sediments is dominated by waves and longshore currents
[image] |
|
|
Term
| Describe the formation and process of how a hurricane forms and works. |
|
Definition
| Forms from hot ocean water (about 80*F); The rate at which water evaporates gets to a critical point at the surface and rises with high humidity. It cools as it goes up and condenses. Condensation of water creates a lot of energy and rain and heat. The air heats up again and goes higher until air cannot rise anymore (about 20-50km). Air pressure below drops catastrophically. When air pressure drops it sucks in air all around. The air that rushes in completes the cycle and makes the process self-sustaining. |
|
|
Term
| Hurricane Diagram (not a question, just for help in understanding the process described in FC #101) |
|
Definition
|
|
Term
| Where do hurricanes dissipate and why? |
|
Definition
| Dissipate on land or at a latitiude of 45* or 50* because there is no more hot, humid air available |
|
|
Term
| How does global warming relate to hurricanes? |
|
Definition
| causes more frequent and more destructive hurricanes |
|
|
Term
| Besides wind damage and rain, what is a major threat posed by hurricanes? |
|
Definition
| Storm surges, which is a sudden and dramatic rise in sea level |
|
|
Term
| What are the two possible causes for storm surges? |
|
Definition
| either the wind pushing on the water or the swelling of sea surface caused by falling atmospheric |
|
|
Term
| Many present-day landforms were either carved by the glaciers of or affected by the colder and wetter climate of which period? |
|
Definition
|
|
Term
| When was the Pleistocene period? |
|
Definition
| 2 million to 10,000 years ago |
|
|
Term
| What conditions must be present for a glacier to form? |
|
Definition
| the amount of snow that accumulates in winter is more than can melt in the summer |
|
|
Term
| What is a glacier, anyway? |
|
Definition
| a solid, moving sheet of ice |
|
|
Term
| What do crevasses in glacial ice indicate? |
|
Definition
| irregularities in the motion of ice |
|
|
Term
|
Definition
| debris of all sorts (including mineral sediment) transported by glaciers
[image] |
|
|
Term
| What is a medial moraine? |
|
Definition
| If one or more tributary glaciers coalesce with the main glacier the lateral moraines unite to form trains of debris on the surface of the glacier at or near its center
[image] |
|
|
Term
| What is a terminal/end moraine? |
|
Definition
| When equilibrium is maintained between the melting of a glacier and its forward advance, the debris carried on, within, and dragged along the bottom is deposited at a point and builds up a heterogeneous mass of the transported material called the terminal moraine. If a glacier is slowly retreating and makes successive halts farther and farther up the valley, a series of terminal moraines are formed which are called recessional or retreating moraines.
[image] |
|
|
Term
| What are the most characteristic features of glacial erosion? |
|
Definition
|
|
Term
| What is a glacial trough? |
|
Definition
| Glaciers transform v-shaped stream valleys to u-shaped glacial troughs by erosion. A U-shaped valley is a type of glacial trough. |
|
|
Term
| What is a hanging valley? |
|
Definition
| Tributary glaciers are often smaller than the main glacier and do not cut as deeply. When the ice melts, these shallower glacial troughs lead into the deeper main trough, leaving hanging valleys. Waterfalls are common features of hanging valleys (e.g. Bridal Veil Falls in Yosemite; below).
[image] |
|
|
Term
|
Definition
| A knife-edged rock divide between two glacial cirques
[image] |
|
|
Term
|
Definition
| A steep-walled semicircular basin in a mountain caused by glacial erosion. After glaciation, the depression may contain a lake.
[image] |
|
|
Term
| here's a good picture of a cirque with a tarn in the center |
|
Definition
|
|
Term
|
Definition
| a lake in the center of a cirque
[image] |
|
|
Term
| What's a horn, and what's a fjord? |
|
Definition
| A horn is just a peak, and a fjord is a glacial valley that has been invaded by the sea. |
|
|
Term
|
Definition
| lakes that form in a shallow basin or bowl shaped depression that was formed when a large block of ice was buried in outwash. Upon melting and dewatering of the sediment the hole left by the block may become a kettle-lake or a kettle-depression. |
|
|
Term
| kettle lake formation diagrams |
|
Definition
|
|
Term
|
Definition
| a long, narrow ridge of sediment left after the melting of a glacier
[image] |
|
|
Term
| What are Pleistocene Pluvial Lakes? |
|
Definition
| HUGE lakes that existed during the Ice Age. (e.g. Great Basin, Lake Bonneville that covered all of the Great Salt Lake and the salt flats) |
|
|
Term
|
Definition
*low rainfall (less than 25 cm per year)
*evaporation greater than precipitation
*limited biological productivity that is a consequence of the first two points
*many deserts are not sandy; some are just bare rock like Death Valley
*some deserts are cold, like Great Basin, Nevada |
|
|
Term
|
Definition
| dry valleys that are not covered in snow, because deserts have little precipitation |
|
|
Term
| What are subtropical deserts? |
|
Definition
| deserts located 30*N and S of the equator and controlled by atmospheric circulation, which is determined by latitude; Ex. Sahara, Outback, Arabia, etc. |
|
|
Term
| What are continental interior deserts? |
|
Definition
| deserts that form from being so far away from the ocean and humidity |
|
|
Term
| Why do coastal deserts form? |
|
Definition
| Cold ocean (longshore) currents reduce evaporation from the ocean, which reduces precipitation on the coast; winds blowing landward are dry; only possible source of rainfall is thus non-existant |
|
|
Term
| In coastal deserts, where do the few plants that can be found obtain water? |
|
Definition
| an abundance of fog that the plants are adapted to extracting water molecules from |
|
|
Term
| What is unique about some meteorological stations in Chili that have existed since the 1800s? |
|
Definition
| They have never, in all the 200 yrs of their existence, seen a single drop of rain. |
|
|
Term
| Why do rain-shadow deserts form? |
|
Definition
| precipitation is low because air from the ocean is blocked by mountains
[image] |
|
|
Term
| What are the four deserts in North America? |
|
Definition
| Chihuahua, Sonoran, Mojave, Great Basin |
|
|
Term
| Describe the Chihuahua desert. |
|
Definition
| located in Mexico, Arizona, New Mexico, Texas; has the highest biodiversity of any desert in the world; identifiable by the Agavi plant from which tequila is made
[image] |
|
|
Term
| Describe the Sonoran desert. |
|
Definition
| located in S. Arizona, California, Nevada, Baha-Mexico; identifiable by the big saguaro cactus
[image] |
|
|
Term
| Describe the Mojave desert. |
|
Definition
| located in S. California, S. Nevada; identifiable by the Joshua Tree, also called the Yucca
[image] |
|
|
Term
| Describe the Great Basin desert. |
|
Definition
locate mostly in Nevada; a cold rain-shadow desert; identifiable by sagebrush
http://www.laspilitas.com/comhabit/pictures/big_basin_sage.jpg |
|
|
Term
| What is the cheif erosional agent in deserts? |
|
Definition
|
|
Term
|
Definition
| deep and narrow valleys carved by temporary streams |
|
|
Term
| What does the wind do as an erosional agent in deserts? |
|
Definition
| it modifies the landscape and gives details |
|
|
Term
| What allows massive erosion during torrential downpours in a desert? |
|
Definition
|
|
Term
| How much rain does Death Valley receive per year and in what timespan? |
|
Definition
| 1/2 inch of rain in a 15 minute shower |
|
|
Term
| Where do alluvial fans form? |
|
Definition
where the gradient of the streams decreases and the sediment load is deposited
http://earthobservatory.nasa.gov/Newsroom/NewImages/Images/aster_artII_alluvial.jpg |
|
|
Term
| How does coalescence of alluvial fans form? |
|
Definition
| through merging bajadas that gradually smother the mountain ranges (which are the sediment sources) |
|
|
Term
|
Definition
| Sloping, coalescing, spreading masses of gravel and sand deposited by streams as they emerge from narrow mountain valleys, and extending from the mountain base into the surrounding valley.
[image] |
|
|
Term
|
Definition
| flat even area of salt and mud flats where fine grained material is deposited from running water in a desert
[image] |
|
|
Term
| Why is Racetrack Playa in Death Valley so named? |
|
Definition
| because large rocks move by themselves and leave long tracks more or less parallel to one another
[image] |
|
|
Term
| What are eolian sediments? |
|
Definition
| sand dunes; eolian because they move by wind |
|
|
Term
| What do the types of dunes depend on? |
|
Definition
| depend on predominant wind direction, amount of sand, and plant life |
|
|
Term
| What are the characteristics of trasverse dunes? |
|
Definition
wind in one direction perpendicular to dune and a lot of sand
http://www.nps.gov/grsa/resources/images/transverse_diag.gif |
|
|
Term
| What are the characteristics of parabolic dunes? |
|
Definition
| one direction of wind and plants
[image] |
|
|
Term
| What are the characteristics of barchan dunes? |
|
Definition
| wind in one direction and little sand
[image] |
|
|
Term
| What are the characteristics of longitudinal/sees dunes? |
|
Definition
| When barchan dunes become highly elongated, they may form into longitudinal dunes, also known as linear dunes. In other parts of the world, such as in Africa, great fields of longitudinal dunes can dominate the landscape for hundreds of miles.
[image] |
|
|
Term
| What are the characteristics of star dunes? |
|
Definition
| Wind blowing from all directions
[image] |
|
|
Term
| What are some reasons for desertification? |
|
Definition
*replacing native grasslands w/ crops
*overgrazing
*depletion of groundwater for irrigation and urban growth
*soil salinization caused by evaporation of irrigation water
*global climate change
***In short: OVERPOPULATION |
|
|
Term
| True or False? The average concentration of most mineral resources in the Earth's crust is lower than what is required to extract them at a profit. |
|
Definition
|
|
Term
| What is an ore deposit, or mineral reserve? |
|
Definition
| a volume of rock in which a mineral resource has been concentrated enough to make its extraction economically feasible |
|
|
Term
| What does the concentration factor required to generate and ore dposit depend on? |
|
Definition
*average abundance in the crust
*location of the ore deposit
*technology available
*how much we are willing to pay for the resource |
|
|
Term
| What is significant about the fact that mineral resources are unevenly distributed throughout the world? |
|
Definition
| This leads to a full spectrum of human behavior, from friendly international trade to total war. The US imports much of its mineral raw materials. |
|
|
Term
|
Definition
| type of igneous mineral deposits characterized by coarse grained granitic rocks that is a major source of many gemstones and light strategic metals (Le, Be) |
|
|
Term
| What are layered igneous intrusions? |
|
Definition
| mineral deposits charachterized by settling of heavy minerals during crystallization of magmas; only source of chromium, nickel, and platinum |
|
|
Term
| What are hydothermal deposits? |
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Definition
| Igneous mineral deposits characterized by circulation of hot water driven by magmatic heat; major sources of copper, silver, gold, zinc, lead, molybdenum |
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Definition
| Igneous mineral deposits characterized by explosive eruptions that transport very deep rocks to the surface; only primary source of diamonds |
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Definition
| Sedimentary mineral deposits characterized by evaporation of water from the ocean or salt lakes; major source of table salt, gypsum, borates, nitrates, phosphates |
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Term
| What are banded iron formations? |
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Definition
Sedimentary mineral deposits characterized by change in the chemistry of sea water triggered by rise of oxygen 2 Ga ago'; only source of commercial iron
no oxygen >> Fe 2+ = Ferrous iron, soluble
W/ oxygen >> Fe 3+ = Ferric iron, insoluble
banded iron formations are only found in Canada, Australia, Brazil, Southern Africa |
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Definition
| Sedimentary mineral deposits characterized by mechanincal accumulation of dense minerals by running water; important source of gold, diamonds, tin |
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Definition
| Weathering mineral deposits characterized by enrichment of aluminum in soild by leaching of all other elements in tropical climates; only commercial source of aluminum; found in Jamaica and Australia |
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Term
| What is land reclamation? |
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Definition
| process of restoring the land to conditions as close as possible to what it was before mining: cleaning, backfilling, restoring slopes, planting |
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