Transcript Chapter 16: The Earth and Its Crustal Resources

Structure of the earth

layered sphere
inner core:
 outer core
 mantle
 crust
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 continental
- felsic
 oceanic - mafic
plate tectonics
surface is made of plates that
move around and bump into each
other
 effects
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earthquakes
 volcanoes
 mountains
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rocks and minerals
minerals: building blocks of rocks
 rocks
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 rock
cycle
 how
rocks form
 how they relate to each other
 igneous
 sedimentary
 metamorphic
economic minerology
resources & reserves - chapt 8
 ore
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economic deposit (includes host material)
 examples
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 gold
- 0001% (10 ppm)
 iron - 20%
metals - uses and distribution - p 359
 nonmetals
 strategic minerals
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mineral extraction
mining techniques
 processing
 effects
 response
 conservation
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recycling
 substitution
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geologic hazards
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outlook
prediction - date, time, magnitude
 forecast - likelihood of occurrence,
magnitude
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earthquakes
faults - energy stored and released
 effects
 magnitude & intensity
 human impact
 prediction and forecast
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volcanoes
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products
lava
 ash
 gas
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effects
 human impact - none known
 prediction and forecast
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floods
river leaves its banks
 effects
 human impact
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increased drainage basin efficiency
 floods are higher and sooner
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prediction and forecast
landslides
slope moves downhill
 human impact
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oversteepen
 undercut
 add weight
 add water
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prediction and forecast
the coast
high energy environment
 flooding and erosion
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Weather & Climate
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weather
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physical conditions of the atmosphere
at a given place and time
may rapidly fluctuate
climate
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long-term weather patterns
average conditions
fluctuates gradually
atmosphere
“ocean of air”
 composition - table p 375
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N2 - 78%
 O2 - 21%
 Ar - 1%
 CO2 - 0035%
 H2O - 0 to 4%
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development of the atmosphere
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early - 4.5 to 3.5 BYA
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3.5 to 1.8 BYA
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emitted by volcanoes
no free oxygen
water forms oceans
CO2 dissolves into the water
life converts the CO2 to organic material, rock,
and O2
oxygen intermittently present in ocean
18 BYA to present
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O2 gradually increased
2% of atmosphere about 550 MYA
layered - fig p 366
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troposphere
 75%
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of atmosphere by mass
stratosphere
 ozone
mesosphere
 thermosphere
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 lower
part - ionosphere
sun’s energy
distribution - fig p 377
 work
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energy changes from high quality to low
quality (infrared)
 “greenhouse”
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reradiated from surface to clouds and back
 cycling of energy between surface and atmosphere
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stored in oceans and atmosphere by
water
 used by plants
 moves as wind
 moves as ocean currents
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weather
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effects
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driving forces
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sun : uneven
distribution of
heat
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equator get more
energy/unit area
earth’s rotation
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coriolis effect deflects moving
air
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circulation patterns - fig p
379
convection cells - fig p 378
jet streams - fig p 380
frontal weather - fig p 380
cyclonic storms - fig p 382
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hurricanes & typhoons
seasonal winds - fig p 383
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monsoons
weather modification
can’t do much
 initiation of precipitation
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El Nino/ Southern Oscillation
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figure - p 386
periodic, dramatic change in weather
patterns
related to equatorial winds and ocean
currents in the Pacific Ocean
effects: shift in rainfall, alteration of
ocean currents
climate change
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trends & patterns - fig p 384
rate
causes
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effects - figs p 388 & 389
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greenhouse gases - fig p 387
moving continents
natural & human
movement of climatic zones
changing rainfall patterns
changing lengths of seasons
more dramatic weather?
solutions?
Air pollution
 foul,
unclean air
 120 million metric tons of air
pollution/yr released in US
sources
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natural
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esp. in rural areas
volcanoes
sea spray
forest fires
plants
viruses
dust
methane (from
digestion)
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human
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up to 90% of total in
cities
pollutant type
primary - released as
harmful
 secondary - modified
in the air
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source type
fugitive
 point
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conventional/criteria pollutants
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regulated in Clean Air Act of 1970
figs p 399, 400, 401
sulfur compounds
nitrogen compounds
carbon oxides
particulates
VOCs (hydrocarbons)
photochemical oxidants
metals and halogens (including Pb)
unconventional/non-criteria
pollutants
regulated
 asbestos
 PCBs
 aesthetic degradation
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noise
 odor
 light
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indoor
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concentrated
smoking
asbestos
plastic emissions
radon
chemicals
indoor fires
climate, topography, and
atmo. processes
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temp inversions - fig p 405
urban heat islands & dust domes
long range transport - fig p 406
stratospheric ozone - fig p 406
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formation
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oxygen altered by UV
destruction - fig p 407
by UV
 by Cl from CFCs
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effects of air pollution
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types of effects
chronic vs acute
 toxic
 diseases
 hormonal
 synergistic
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human health
 plant pathology
 acid deposition - fig p 410
 visibility
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control of air pollution
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move sources away
taller smoke stacks
particulate removal - fig p 413
sulfur removal
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nitrogen oxide control
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fuel switching & fuel cleaning
limestone injection & fluidized bed combustion - fig p
414
flue gas desulfurization & sulfur recovery
catalytic converters (ruined by Pb)
hydrocarbon controls
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PCV in cars
Laws - clean air acts
1963
 1970
 1990
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marketing pollution rights
 ozone protection
 auto emissions
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currently under review by Supreme
Court
current conditions/future
prospects
 improving
in first world - fig p
418
 degrading in second and third
world
Water resources
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importance
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source
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essential for life
60% of body
70% of Earth’s surface
volcanoes
comets
hydrologic cycle - fig p 424
water distribution - table p 426
oceans - 97%
 glaciers/snow - 2%
 groundwater - 0.28%
 lakes/reservoirs
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 fresh
- 0.009%
 saline - 0.007%
also soil moisture - 0.005%
 atmo - 0.001%
 wetlands - 0.0003% (typo in book)
 rivers and streams - 0.0001%
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groundwater movement
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fig p 428
infiltration
zone of aeration (soil moisture)
water table
zone of saturation
water moves under pressure of gravity
through pores in the rock/sediment
(rarely in cracks
surface water movement
2/3 - seasonal floods
 1/3 - stable runoff
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freshwater sources
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runoff
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direct
storage and redistribution
groundwater
alternatives
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desalinization
cloud seeding
icebergs
drought
long-term shortages
 cyclic
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types of water use
withdrawal - total removed
 consumption - not returned
 degradation - returned in a poorer
state
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quantities used - graph p 431
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agriculture
commercial/industrial
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cooling water for power plants
metal refining
petroleum refining
paper
domestic
public
lost
implication/effects of use
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groundwater - best source
degradation
 drawdown of water table - fig p 435
 mining
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surface water reservoirs
evaporation
 leakage
 siltation
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in-stream users
management
 watershed
management
 conservation by users
 pricing
Water pollution
 degradation
of water quality
 sources
 point
 non-point
 atmosphere
 in-stream
users
water pollution types (table p 449)
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infectious agents - fig p 452
oxygen-demanding wastes - fig p 451
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BOD
examine - dissolved oxygen & life forms present
nutrients
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eutrophication - nutrients stimulate growth
vegetation chokes water
clarity decreases
upon death - produce oxygen demanding waste
examine - nitrogen and phosphorous content
water pollution types
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table p 449
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toxic inorganics
organic chemicals
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pesticides
petrochemicals - LUST
pharmaceuticals
sediment
thermal pollution
current water quality
 fig
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p 457
1972 clean water act
regulated point sources
 make all waters fishable and
swimmable
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current problems
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feedlots
non-point source
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ag runoff
storm sewers
USTs
landfills
septic/sewage treatment
developing countries
other water pollution problems
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groundwater and drinking water supplies
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fig p 460
many sources
filtration capacity is limited
contamination difficult to remove
oceans - fig p 462
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trash
ag runoff
nets
petroleum spills
natural
 human
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pollution control
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source reduction
land management
human waste
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septic tanks & lagoons - fig p 465
municipal sewage treatment - fig p 466
primary - filtering
 secondary
 tertiary
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other methods
septic effluent to central collection
 wetland use
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laws - table p 469
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clean water act
1972 - original
 amending and reauthorizing
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safe drinking water act
regulates municipal supplies
 mandates testing and imposes limits
 CERCLA/superfund
 Great Lakes water quality agreement
 London dumping convention
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