chapter 1 fundamental concepts. earth formed from a solar nebula: 4.6 ga life on earth began: 3.5...
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Chapter 1Chapter 1
FUNDAMENTAL CONCEPTSFUNDAMENTAL CONCEPTS
EarthEarth formed from a solar nebula: 4.6 Ga formed from a solar nebula: 4.6 Ga LifeLife on Earth began: 3.5 Ga on Earth began: 3.5 Ga GeologyGeology: Science of processes related to:: Science of processes related to:
Composition, structure, history and life of Composition, structure, history and life of EarthEarth
Environmental Geology:Environmental Geology: Studies entire spectrum of human interactions Studies entire spectrum of human interactions
with the physical environmentwith the physical environment It is geology applied to:It is geology applied to:
Solve conflicts in land useSolve conflicts in land use Minimize environmental degradationMinimize environmental degradation Maximize the benefits of natural Maximize the benefits of natural
resourcesresources
EarthEarth
Earth HistoryEarth History
Figure 1.AFigure 1.A
Inception: Inception: 4.6 Ga4.6 Ga
Change Change over time: over time: Environment Environment and and bioextinctionbioextinction
Fig. 10.9
The geologic column
The composite stratigraphic column was assembled from incomplete sections found in different places across the globe. By correlation, the strata in the different columns can be stacked in a sequence that spans almost all of Earth history.
No other planet in the solar system No other planet in the solar system currently has the right currently has the right chemical and chemical and physical mixphysical mix needed to support life needed to support life
No conclusive evidence of No conclusive evidence of lifelife existing existing elsewhere in the universe has yet been elsewhere in the universe has yet been discovered as far as we knowdiscovered as far as we know
Its size, gravity, magnetic field, water, Its size, gravity, magnetic field, water, distance to the Sun, are perfect!distance to the Sun, are perfect!
Earth is UniqueEarth is Unique
Seek to understand all processes that operate on and Seek to understand all processes that operate on and inside the Earthinside the Earth
Study:Study: Our planetOur planet’’s long historys long history Water bodies (rivers and lakes)Water bodies (rivers and lakes) Hazardous processes such as earthquakes, volcanic Hazardous processes such as earthquakes, volcanic
eruptions, flood, and landslideseruptions, flood, and landslides Rocks/mineralsRocks/minerals
What Do Geologists What Do Geologists Do?Do?
Earth Environment (1)Earth Environment (1)
James HuttonJames Hutton (1785): (1785): Earth as a Earth as a superorganismsuperorganism
James LovelockJames Lovelock:: Gaia hypothesis Gaia hypothesis Earth is an organismEarth is an organism Life significantly affects the Earth’s Life significantly affects the Earth’s
environmentenvironment Life modifies the environment for the Life modifies the environment for the
betterment of lifebetterment of life Life deliberately or consciously controls Life deliberately or consciously controls the global environmentthe global environment
Earth Environment (2)Earth Environment (2)
EarthEarth:: Dynamic, alive, and complexDynamic, alive, and complex
Everything aliveEverything alive:: With a beginning and an endWith a beginning and an end
Earth environment as a total, as a wholeEarth environment as a total, as a whole
Prolong Earth’s sustainable healthy lifeProlong Earth’s sustainable healthy life Environment monitoringEnvironment monitoring Environment problemsEnvironment problems
mapping and analysismapping and analysis prevention and protectionprevention and protection
Environmental SciencesEnvironmental Sciences
EnvironmentEnvironment: : A complex system with physical, A complex system with physical, biological, geological, ecological, and geopolitical biological, geological, ecological, and geopolitical aspectsaspects
Requires multidisciplinary researchRequires multidisciplinary research: : Environmental geology, environmental chemistry, Environmental geology, environmental chemistry, global climate change, biological diversity and global climate change, biological diversity and ecosystems, environmental economics, ecosystems, environmental economics, environmental ethics, environmental law, etc.environmental ethics, environmental law, etc.
Environmental crisisEnvironmental crisis: : Population, environmental Population, environmental hazards, resource limitations and contaminations, hazards, resource limitations and contaminations, environment ownership (both in space and time)environment ownership (both in space and time)
Why environmental geology?Why environmental geology?
Earth: Earth: Source for habitats and resourcesSource for habitats and resources
There is a geologic aspect in every There is a geologic aspect in every environmental conditionenvironmental condition
Environmental geology:Environmental geology: Applied geologyApplied geology To better understand environmental To better understand environmental problemsproblems Geologic knowledge for problem solvingGeologic knowledge for problem solving Optimize the use of resources to Optimize the use of resources to maximize maximize environmental benefits for the environmental benefits for the societysociety
Earth MaterialsEarth Materials (rocks, minerals, soils) (rocks, minerals, soils) formation, effects on health, as resource or wasteformation, effects on health, as resource or waste
Natural HazardsNatural Hazards floods, landslides, quakes, volcanic eruptionsfloods, landslides, quakes, volcanic eruptions
minimize loss of lifeminimize loss of life
Land for Site SelectionLand for Site Selection Land use planning, environmental Impact Land use planning, environmental Impact
analysisanalysis Hydrologic Processes of surface/ground Hydrologic Processes of surface/ground
waterwater Water resources, pollutionWater resources, pollution
Global Geologic ProcessGlobal Geologic Process Atmospheric, hydrologic, and lithosphericAtmospheric, hydrologic, and lithospheric
Environmental Geology Involves Environmental Geology Involves Study of:Study of:
Landslide is a red flag for future urban development
1.1. Human Population GrowthHuman Population Growth Environmental impact = (individual impact X population)Environmental impact = (individual impact X population)
2.2. SustainabilitySustainability This is an objective. Ensure that future generations have This is an objective. Ensure that future generations have
equal opportunity to the planet’s resourcesequal opportunity to the planet’s resources Limitation of ResourcesLimitation of Resources
3.3. Concept of Earth having Concept of Earth having system/subsystemssystem/subsystems
4.4. Hazardous Earth ProcessesHazardous Earth Processes5.5. Scientific knowledge and valuesScientific knowledge and values
6.6. Other concepts:Other concepts: UniformitarianismUniformitarianism Our obligation to the futureOur obligation to the future
Concepts of Environmental Science
Pollution Pollution (air, water, soil) due to garbage (air, water, soil) due to garbage disposal, farming, and fuel burningdisposal, farming, and fuel burning
Water suppliesWater supplies (Earth population grows by (Earth population grows by more than 100 M each year). Important for more than 100 M each year). Important for desert citiesdesert cities
Disposal of radioactive wasteDisposal of radioactive waste
Effect of other hazardous wasteEffect of other hazardous waste (chemicals (chemicals like pesticide) like pesticide) on air, groundwater, and soilon air, groundwater, and soil
Waste from mining activityWaste from mining activity (coal, metal ores) (coal, metal ores)
Concerns of Environmental Concerns of Environmental GeologyGeology
Geologic hazards (Geologic hazards (geohazards): geohazards): Earth processes harmful to humans and their Earth processes harmful to humans and their property, e.g., earthquake, volcanic eruption, property, e.g., earthquake, volcanic eruption, flooding, slidesflooding, slides
Coastline erosionCoastline erosion
Sea level rise due to global warmingSea level rise due to global warming (risk for (risk for
coastal cities)coastal cities)
Acid rainAcid rain (due to fuel burning; e.g. S-bearing coal (due to fuel burning; e.g. S-bearing coal
burning)burning)
Ozone depletionOzone depletion; global warming; global warming
Concerns of Environmental Concerns of Environmental GeologyGeology
COCO2 2 Levels are Levels are IncreasingIncreasing
Acid Rain Acid Rain increasing increasing because because of of burning burning coal and coal and other other fossil fossil fuelsfuels
Ozone Ozone DepletiDepleting ng because because of man of man made made chemicchemicalsals
Mean Temperature is Rising Mean Temperature is Rising because of higher CObecause of higher CO22 levels levels
Figure 1.Figure 1. Grinnell Glacier Grinnell Glacier in Glacier National Park, in Glacier National Park, Montana; photograph by Montana; photograph by Carl H. Key, USGS, in Carl H. Key, USGS, in 1981. The glacier has been 1981. The glacier has been retreating rapidly since the retreating rapidly since the early 1900's. early 1900's. The arrows point to the The arrows point to the
former extent offormer extent of the the glacier in 1850, 1937, and glacier in 1850, 1937, and 1968.1968.
The worldwide shrinkage of The worldwide shrinkage of mountain glaciers is mountain glaciers is thought to be caused by a thought to be caused by a combination of a combination of a temperature increase from temperature increase from the Little Ice Age, which the Little Ice Age, which ended in the latter half of ended in the latter half of the 19th century, and the 19th century, and increased greenhouse-gas increased greenhouse-gas emissions.emissions.
Sea Level is RisingSea Level is Rising
PPopulation growing opulation growing exponentiallyexponentially
The population growth is defined by:The population growth is defined by:
PPtt = P = Poo e ertrt
PPtt is the population at a given time t is the population at a given time t
PPoo is the original population is the original populationrr is the growth rate (per time; t is the growth rate (per time; t-1 -1 or 1/t)or 1/t)tt is time (t) is time (t)ee is the base of the natural log (i.e., is the base of the natural log (i.e., lnln) function ) function (e(e11=2.718)=2.718)
Unit of P is # (i.e., number of) of people because: Unit of P is # (i.e., number of) of people because: (# of people) = (# of people) e(# of people) = (# of people) e (1/t)(t)(1/t)(t)
The The raterate (i.e., slope) of growth (i.e., people/time) of (i.e., slope) of growth (i.e., people/time) of the population increases with time (i.e., is not the population increases with time (i.e., is not constant)constant)
In simple math the eqn. for exponential growth is:In simple math the eqn. for exponential growth is:
PPtt/P/Poo=10=100.3n0.3n where n is the umber of doubling times where n is the umber of doubling times
Exponential Growth RateExponential Growth Rate
Year Year (t)(t) 00 11 22 33 4 4 Population (PPopulation (Ptt)) ppoo=1=1 pptt=2=2 p ptt=4=4 pptt=8=8 p ptt=16=16Rate of growthRate of growth 00 11 22 44 8 8
Starting at an arbitrary time, the population is:Starting at an arbitrary time, the population is: 2 times (i.e., 22 times (i.e., 211) as large after each doubling time t) as large after each doubling time tDD
4 times (i.e., 24 times (i.e., 222) as large after 2 doubling times, 2t) as large after 2 doubling times, 2tDD
8 times (i.e., 28 times (i.e., 233) as large after 3 t) as large after 3 tD D
Population Population Number of doubling times (t Number of doubling times (tDD) passed) passed 1 = 21 = 20 0 == PPoo 00
2 = 22 = 21 1 = P= Ptt 11 In general: In general: PPt t = P= Poo22n n = P= Poo 10 100.3n0.3n
4 = 24 = 22 2 = P= Ptt 22 where n = t where n = tDD
8 = 28 = 23 3 = P= Ptt 3 Given the ratio of 3 Given the ratio of PPt t = P= Po o we can find twe can find tDD
22ttDD
= P= Ptt n n Given Given PPo o and doubling time, we can find Pand doubling time, we can find Ptt Exponential growth occurs by an excess of births over deathExponential growth occurs by an excess of births over death As the absolute number of people increases, the number of As the absolute number of people increases, the number of
people added each year will increase also, yielding a concave people added each year will increase also, yielding a concave upward curveupward curve
Start with 0 people. Assume that after a year each person has to babies. What is the rate of growth?
Population “time bomb”: because of exponential growthEarth’s carrying capacity is limited:
More resources used, more land space occupied, more waste produced!
Assuming exponential growth Growth rate (r): is measured as %/yr Doubling time (tD) is a function of growth rate (r): tD
=70/r
Examples: If the growth rate r is 0.5%/yr, what is the doubling time
(tD) assuming exponential growth: tD = 70/0.5 = 140 year
If inflation is 8%/yr, how long does it take for the cost of living to double?
tD = 70/8 = 9 yr
Overpopulation is number one environmental problem!
If the ratio of U.S. population in year 2090 (i.e., If the ratio of U.S. population in year 2090 (i.e., PPtt) to that of 1850 (i.e., P) to that of 1850 (i.e., Poo) is 16, find: ) is 16, find: How many doubling times have passed (i.e., n)How many doubling times have passed (i.e., n) Duration of each doubling time Duration of each doubling time % per year increase of the population (i.e., % per year increase of the population (i.e.,
growth rate)growth rate)PPt t = P= Po o 22
n n = P= Poo 10 100.3n0.3n
PPtt/P/Po o = 10= 100.3n0.3n
16 =16 = 10100.3n 0.3n Now take logarithm of both sides:Now take logarithm of both sides:log16 = 0.3n log10log16 = 0.3n log10 ((Note: log10 = 1Note: log10 = 1))log2log244 = 0.3n = 0.3n ((Note: logxNote: logxn n = nlogx= nlogx))4log2 = 0.3n4log2 = 0.3nn = 1.2/0.3 = 4 doubling timesn = 1.2/0.3 = 4 doubling times2090-1850 = 240 years2090-1850 = 240 years240/4 = 60 (duration of each doubling time in years) 240/4 = 60 (duration of each doubling time in years)
ttDD = 60 = 70/%r = 60 = 70/%r% growth rate = 1.17 (i.e., per year increase)% growth rate = 1.17 (i.e., per year increase)
Example 1 - Simple MathExample 1 - Simple Math
If the population of a country doubles its size each 40 years (i.e., tIf the population of a country doubles its size each 40 years (i.e., tD D = 40), = 40), and if the population in 1980 is 10x10and if the population in 1980 is 10x10 6 6 heads (i.e., P heads (i.e., Poo), calculate the:), calculate the:
population in the year 2100 (i.e., Ppopulation in the year 2100 (i.e., Ptt)) % per year increase of the population (growth rate per year)% per year increase of the population (growth rate per year)
PPt t = P= Poo22n n =P=Poo 10 100.3n0.3n
PPtt/P/Po o = 10= 100.3n0.3n
Time period: 2100-1980 = 120 yearsTime period: 2100-1980 = 120 yearsn = 120/40 = 3n = 120/40 = 3PPt t = P= Po o 22n n = P= Po o 223 3 = P= Po o 10100.3(3)0.3(3)
PPtt = P = Po o 10100.90.9
PPtt = 10x10 = 10x106 6 (10(100.90.9))log Plog Ptt = log10 + 6log10 + 0.9log 10 = log10 + 6log10 + 0.9log 10log Plog Ptt = 1 + 6 + 0.9 = 7.9 = 1 + 6 + 0.9 = 7.9PPtt = 10 = 107.97.9 (population in the year 2100)(population in the year 2100)
ttD D = 0.693/r= 0.693/r 40 = 70/% 40 = 70/% growth rate per year: % = 1.75growth rate per year: % = 1.75
Example 2Example 2
Human Population GrowthHuman Population Growth Rate of growth increased due to better:Rate of growth increased due to better:
agriculture, sanitation, medicine, energy agriculture, sanitation, medicine, energy sourcessources
OverpopulationOverpopulation Started few centuries agoStarted few centuries ago Is a global problemIs a global problem
Population Grows ExponentiallyPopulation Grows Exponentially
OverpopulationOverpopulation
Exponential human population Exponential human population growthgrowth
Scenario:Scenario:A student A student starts a job starts a job with 1 cent for with 1 cent for the first day. the first day. Salary is Salary is doubled each doubled each day for 31 day for 31 days!days!
At the end of At the end of the month, the the month, the student is a student is a multi-multi-millionaire!millionaire!
World’s population was ~ 300 M about 2 ka It apparently didn't increase much up to AD 1000 It reached 800 million by the beginning of the Industrial
Revolution in 1750 Average growth rate=0.13%/yr in 750 yrs (1000-1750) By 1800, population reached one billion while the second
billion was reached by 1930 (i.e., in 130 yrs) Average growth rate = 0.53%/yr From 1930 to 1960, population reached 3 billion (in 30
yrs) Average growth rate = 1.36 %/yr By 1974, the fourth billion was reached (in 14 yrs) Average growth rate = 2.1% from 1960 to 1974 From 1974 to 1990, the mark hit five billion (in 16 yrs) Average growth rate slowed to 1.4%
Growth of World’s PopulationGrowth of World’s Population
World annual population increase peaked in the late 1990s
Uneven growing pace and global distributionUneven growing pace and global distribution
Little access to, or use of, modern family Little access to, or use of, modern family planning methods in less developed countriesplanning methods in less developed countries
AfricaAfrica: Home to a larger share of world : Home to a larger share of world population over next half centurypopulation over next half century
AsiaAsia: : Many nations overpopulatedMany nations overpopulated IndiaIndia, over one third of its population under , over one third of its population under
15 years old, is likely the largest population 15 years old, is likely the largest population by mid centuryby mid century
Population Population Bomb:Bomb:
About to About to Explode?Explode?
Degradation of the environment by Degradation of the environment by pollutionpollution PollutionPollution: Unfavorable alteration of our : Unfavorable alteration of our
surroundings, wholly or largely as a by-surroundings, wholly or largely as a by-product of human actionproduct of human action
Serious shortages of resources (including Serious shortages of resources (including food)food) Is brought by straining Earth’s ability to Is brought by straining Earth’s ability to
provide food, clothing, shelter, and energyprovide food, clothing, shelter, and energy
e.g., on the average, each of us, on a yearly e.g., on the average, each of us, on a yearly basis, uses: basis, uses: 500 kg steel, 25 kg Al, 200 kg 500 kg steel, 25 kg Al, 200 kg saltsalt
Effect of Population on Earth Effect of Population on Earth ResourcesResources
Development of Geologic ProblemsDevelopment of Geologic Problems As homes replace fields in flat areas, As homes replace fields in flat areas,
farming is displaced to hilly regionsfarming is displaced to hilly regions Steeper slopes accelerate soil loss, Steeper slopes accelerate soil loss,
polluting streams with sand and siltpolluting streams with sand and silt
An increased rate of injuries, property An increased rate of injuries, property damage, and loss of life (due to damage, and loss of life (due to geologic hazards)geologic hazards)
Effect of Population on Earth Effect of Population on Earth ResourcesResources
Burning petroleum and coal, which Burning petroleum and coal, which increases the increases the greenhouse effectgreenhouse effect
Intensive farming activities, which have an Intensive farming activities, which have an impact on soil, ground and surface waterimpact on soil, ground and surface water
Production and release of gases Production and release of gases containing chlorine, which destroys containing chlorine, which destroys ozoneozone
Redistribution of water through the Redistribution of water through the construction of giant reservoirs, which construction of giant reservoirs, which changes the distribution of weight at changes the distribution of weight at EarthEarth’’s surface and alters, slightly but s surface and alters, slightly but measurably, the rotation of the Earth on measurably, the rotation of the Earth on its axisits axis
Humans are affecting the Earth Humans are affecting the Earth system:system:
Our daily activities are having Our daily activities are having measurable effects on:measurable effects on: RainfallRainfall ClimateClimate AirAir Water qualityWater quality ErosionErosion Mineral resourcesMineral resources
In North America, we use 20 tons of In North America, we use 20 tons of mineral resources per person/yearmineral resources per person/year
Human Influences …Human Influences …
Is an environmental objective!Is an environmental objective! Goal to ensure that future generations have Goal to ensure that future generations have
equal access to Earth resourcesequal access to Earth resources
Is a long-term objective, achieved over Is a long-term objective, achieved over decades or centuriesdecades or centuries
Requires types of development that:Requires types of development that: Are economically viableAre economically viable Do no harm the environmentDo no harm the environment Are socially justAre socially just
SustainabilitySustainability
Facts about SustainabilityFacts about Sustainability
An evolving conceptAn evolving concept
Expectation and realityExpectation and reality
Criteria variations in space and over timeCriteria variations in space and over time
Long-term implicationsLong-term implications
Requiring careful resources allocation, large-Requiring careful resources allocation, large-scale development of new tech for resource use, scale development of new tech for resource use, recycling, and waste disposalrecycling, and waste disposal
Logging – clear-cut timber harvesting exposes soil, leading to erosion
Possible for the Possible for the renewable resourcesrenewable resources such such as air, water, fish, forest, domesticated as air, water, fish, forest, domesticated stock and wildlife, agricultural productsstock and wildlife, agricultural products
For For non-renewablenon-renewable resources resources, such as , such as fossil fuels and minerals, sustainability is fossil fuels and minerals, sustainability is possible by:possible by: Conservation/RecyclingConservation/Recycling to extend their to extend their
availabilityavailability Finding Finding substitutionsubstitution ( (alternativealternative) for ) for
the materialthe material
Sustainability of Sustainability of ResourcesResources
A A systemsystem is any portion of the is any portion of the universe that can be isolated from the universe that can be isolated from the rest of the universe for observing and rest of the universe for observing and measuring changemeasuring change
The simplest kind to understand is an The simplest kind to understand is an isolated systemisolated system the boundary completely prevents the boundary completely prevents
the exchange of either matter or the exchange of either matter or energyenergy
System ConceptSystem Concept
The nearest thing to an isolated The nearest thing to an isolated system in the real world is a system in the real world is a closed closed systemsystem:: exchanges energy with its exchanges energy with its
surroundings, but not mattersurroundings, but not matter
An An open systemopen system can exchange both can exchange both energy and matter across its boundaryenergy and matter across its boundary
Open and Closed Open and Closed SystemsSystems
SystemsSystems
Energy and materials (like water, carbon, Energy and materials (like water, carbon, and minerals) are transferred from one and minerals) are transferred from one system to anothersystem to another
To a close approximation, Earth is a To a close approximation, Earth is a closed system closed system because: because: Meteorites do come in from space and fall Meteorites do come in from space and fall
on Earthon Earth A tiny trickle of gases leaves the A tiny trickle of gases leaves the
atmosphere and escapes into spaceatmosphere and escapes into space
Earth is comprised of Earth is comprised of four four openopen systems systems
Earth systemEarth system
The atmosphere:The atmosphere: Nitrogen, oxygen, argon, carbon dioxide, and Nitrogen, oxygen, argon, carbon dioxide, and
water vaporwater vapor The hydrosphere:The hydrosphere:
Oceans, lakes, streams, underground water, Oceans, lakes, streams, underground water, snow, and icesnow, and ice
The biosphere:The biosphere: All of EarthAll of Earth’’s organisms, as well as any s organisms, as well as any
organic matter not yet decomposedorganic matter not yet decomposed The geosphere:The geosphere:
The solid Earth from core to surface, The solid Earth from core to surface, composed principally of rock and regolithcomposed principally of rock and regolith
Our PlanetOur Planet’’s s ““Four SpheresFour Spheres”” or or Subsystems (cryosphere is the Subsystems (cryosphere is the fifth)fifth)
..
Earth’s Systems and ChangesEarth’s Systems and Changes
EarthEarth: A dynamic system: A dynamic system
Two engines behind its dynamics:Two engines behind its dynamics: InternalInternal and and externalexternal heat sources heat sources
Five interconnected subsystems:Five interconnected subsystems: lithosphere, atmosphere, hydrosphere, and lithosphere, atmosphere, hydrosphere, and biosphere, cryospherebiosphere, cryosphere
these these subsystems mutually adjustsubsystems mutually adjust
Energy SourcesEnergy Sources
Short-term Short-term changes: Long-changes: Long-lasting adverse lasting adverse effects. effects. Ducktown, TN Ducktown, TN due to mining, due to mining, ~ 100 yrs~ 100 yrs
Earth’s Systems and ChangesEarth’s Systems and Changes
DeforestationDeforestation
Soil erosionSoil erosion
Water and air pollutionWater and air pollution
DesertificationDesertification
Pollution due to mining (minerals, coal, Pollution due to mining (minerals, coal, oil)oil)
Overuse of groundwater and surface Overuse of groundwater and surface water resources (e.g., Aral Sea)water resources (e.g., Aral Sea)
Global Environmental Global Environmental ProblemsProblems
Dying Aral Sea surrounded by salt flats, due to diversion of water for agriculture
The whole Earth behaves like an organismThe whole Earth behaves like an organism
It is a self-regulating network of interdependent It is a self-regulating network of interdependent physical and biological systemsphysical and biological systems
A disturbance (e.g., deforestation) in one part of the A disturbance (e.g., deforestation) in one part of the system (Earth) must result in adjustment in other system (Earth) must result in adjustment in other parts (e.g., global warming)parts (e.g., global warming)
System ApproachSystem Approach
Earth’s Systems and Changes (2)Earth’s Systems and Changes (2)
System conditions: System conditions: OpenOpen vs. vs. closedclosed systems systems
System System input-output analysisinput-output analysis
System changesSystem changes: Types of changes, rates of : Types of changes, rates of changes, scales of changes, etc.changes, scales of changes, etc.
Rates of changeRates of change: Average residence time: Average residence time T = S/F T = S/F (T: residence time, S: total size of stock, (T: residence time, S: total size of stock,
F: average rate of transfer)F: average rate of transfer)
1. 1. Earth: Earth: rocks and mineralsrocks and minerals origin, variety, distribution, and pollution origin, variety, distribution, and pollution
of of soilsoil causes of, distribution, and prediction of causes of, distribution, and prediction of
earthquake/volcanic activityearthquake/volcanic activity cause and prevention of cause and prevention of coastal erosion coastal erosion
and slope failureand slope failure mineral and water resourcesmineral and water resources
Environment influenced by Environment influenced by threethree inter-related variables inter-related variables
2. Air:2. Air:
composition and circulationcomposition and circulation
pollution by human pollution by human activitiesactivities
climateclimate
Environment influenced by Environment influenced by threethree inter-related variables inter-related variables
3. 3. Water:Water:
distributiondistribution
movement and floodingmovement and flooding
range in chemical range in chemical compositioncomposition
pollution by human activitiespollution by human activities
managementmanagement
Environment influenced by Environment influenced by threethree inter-related variables inter-related variables
HH22O circulates freely among theO circulates freely among the:: atmosphere (as gas, e.g., vapor)atmosphere (as gas, e.g., vapor) ground surface (as solid, e.g., ice, ground surface (as solid, e.g., ice,
and liquid water)and liquid water) subsurface (liquid water)subsurface (liquid water) Solid surface material are:Solid surface material are: carried to the ocean by runoff (as carried to the ocean by runoff (as
suspended, dissolved, and bed loads)suspended, dissolved, and bed loads) carried to the atmosphere by wind carried to the atmosphere by wind
(as dust)(as dust)
Inter-relationship of Inter-relationship of atmosphere, atmosphere, hydrosphere, & lithospherehydrosphere, & lithosphere
The movement of materials is The movement of materials is continuouscontinuous
There are two key aspects to cycles:There are two key aspects to cycles: The reservoirs in which the materials The reservoirs in which the materials
residereside The flows, or fluxes, of materials The flows, or fluxes, of materials
from reservoir to reservoirfrom reservoir to reservoir
The speed of movement differs The speed of movement differs greatly in different cyclesgreatly in different cycles
Cyclical MovementsCyclical Movements
The hydrologic cycleThe hydrologic cycle Water in EarthWater in Earth’’s hydrospheres hydrosphere
The rock cycleThe rock cycle Rock is formed, modified, Rock is formed, modified,
decomposed, and reformed by the decomposed, and reformed by the internal and external processes of internal and external processes of EarthEarth
The tectonic cycleThe tectonic cycle Movements of plates of lithosphere, Movements of plates of lithosphere,
and the internal processes of Earthand the internal processes of Earth’’s s deep interior that drive plate motionsdeep interior that drive plate motions
Three Most Important Three Most Important CyclesCycles
Is powered by heat from the sunIs powered by heat from the sun
Encompasses the movement of Encompasses the movement of water in the atmosphere, in the water in the atmosphere, in the hydrosphere, on the Earthhydrosphere, on the Earth’’s s surface, and in the Earthsurface, and in the Earth’’s crusts crust
The hydrologic cycleThe hydrologic cycle
Rock is any naturally formed, nonliving, Rock is any naturally formed, nonliving, firm and coherent aggregate of mineral firm and coherent aggregate of mineral matter that constitutes part of a planet.matter that constitutes part of a planet.
The three rock families:The three rock families: Igneous rock:Igneous rock:
Created through the cooling and Created through the cooling and solidification of magmasolidification of magma
Sedimentary rock:Sedimentary rock: Formed from deposits of sedimentFormed from deposits of sediment
Metamorphic rock: Metamorphic rock: Formed by the effects of pressure and Formed by the effects of pressure and
heat on existing rocksheat on existing rocks
Rock CycleRock Cycle
Tectonics is the study of the movement Tectonics is the study of the movement and deformation of the lithosphereand deformation of the lithosphere
When magma rises from deep in the When magma rises from deep in the mantle, it forms new oceanic crust at mantle, it forms new oceanic crust at mid ocean ridgesmid ocean ridges
The lifetime of oceanic crust is shorter The lifetime of oceanic crust is shorter than the lifetime of continental crustthan the lifetime of continental crust The most ancient oceanic crust of the ocean The most ancient oceanic crust of the ocean
basins is only about 180 million years old, and the basins is only about 180 million years old, and the average age of all oceanic crust is about 70 average age of all oceanic crust is about 70 million years oldmillion years old
Tectonic CycleTectonic Cycle
When all oceanic crust sinks back When all oceanic crust sinks back into the mantle, it carries some into the mantle, it carries some water with itwater with it
The water is driven off during The water is driven off during volcanic eruptionsvolcanic eruptions
Some constituents in the hot rock Some constituents in the hot rock (calcium, magnesium) are the same (calcium, magnesium) are the same as those of seawateras those of seawater
Tectonic CycleTectonic Cycle
The other cycles include the The other cycles include the biogeochemical cycles: biogeochemical cycles: CarbonCarbon OxygenOxygen NitrogenNitrogen
Other cyclesOther cycles
COCO22 Cycle Cycle
Predicting Future ChangesPredicting Future Changes
UniformitarianismUniformitarianism The present is the key to the pastThe present is the key to the past The present is the key to the futureThe present is the key to the future Changes of frequency and magnitude: Changes of frequency and magnitude:
Geological processes and human activitiesGeological processes and human activities
Environmental unityEnvironmental unity: Chain of actions and reactions: Chain of actions and reactions
Earth systemEarth system Gaia hypothesis: Earth is a living organismGaia hypothesis: Earth is a living organism Complex and interrelated subsystemsComplex and interrelated subsystems Global perspective on environmentGlobal perspective on environment
Hazardous Earth ProcessesHazardous Earth Processes
Hazardous Earth processes and risk statistics for Hazardous Earth processes and risk statistics for the past two decadesthe past two decades Annual loss of life: About 150,000Annual loss of life: About 150,000 Financial loss: > $20 billionFinancial loss: > $20 billion More life loss from a major natural disaster in More life loss from a major natural disaster in a a developing country (2003 Iran quake, developing country (2003 Iran quake, ~300,000 ~300,000 people)people) More property damage occurs in a more More property damage occurs in a more developed countrydeveloped country
Risk AssessmentRisk Assessment
Hazard identificationHazard identification
Risk assessment (types, probability, and Risk assessment (types, probability, and consequences of impact)consequences of impact)
Critical facility mapping and analysisCritical facility mapping and analysis Economic impact analysisEconomic impact analysis Societal impact analysisSocietal impact analysis Total environmental impact analysisTotal environmental impact analysis
Risk management and mitigationRisk management and mitigation
Risk PerceptionRisk Perception
Public attitude toward risksPublic attitude toward risks
Public acceptance for risksPublic acceptance for risks Threshold for living with dangersThreshold for living with dangers Planning decisions, e.g., floodplain Planning decisions, e.g., floodplain
development, waste disposaldevelopment, waste disposal
Public awareness and collective actionsPublic awareness and collective actions Anticipatory measuresAnticipatory measures Mitigation planningMitigation planning
Scientific Knowledge and Values (2)Scientific Knowledge and Values (2)
3-D environmental problems3-D environmental problems
Changes of environment in the 4-D (time)Changes of environment in the 4-D (time) Expansiveness of geologic timeExpansiveness of geologic time Broad spectrum of geologic processesBroad spectrum of geologic processes Great variations in rates of geologic Great variations in rates of geologic processesprocesses
Humans are super agent of changeHumans are super agent of change Holocene epochHolocene epoch Industrialization and global Industrialization and global environmental environmental changeschanges
Scientific Scientific Knowledge Knowledge and Values and Values
(1)(1)
Figure 1.12Figure 1.12
Science and SolutionScience and Solution
ScienceScience: Accumulated knowledge: Accumulated knowledge
KnowledgeKnowledge: Basis for decision making: Basis for decision making
Scientific methodsScientific methods: Formulate possible : Formulate possible solutions to environmental problemssolutions to environmental problems
Scientific designScientific design: Structure more suitable for : Structure more suitable for certain environmental settingscertain environmental settings
Scientific infoScientific info: Public awareness and : Public awareness and environmental regulationsenvironmental regulations
Applied and Critical Thinking TopicsApplied and Critical Thinking Topics
Do you think the Earth is a living organism? Do you think the Earth is a living organism? Why or Why or why not?why not?
Why did you take this environmental geology Why did you take this environmental geology course?course?
Would an exponential negative growth of Would an exponential negative growth of human human population be a solution to many population be a solution to many environmental environmental problems?problems?
Science can certainly provide solutions to Science can certainly provide solutions to environmental problems, but think of ways environmental problems, but think of ways
that that science science brought aboutbrought about environmental environmental problems.problems.