Chapter 1 FUNDAMENTAL CONCEPTS

 Earth formed from a solar nebula: 4.6 Ga  Life on Earth began: 3.5 Ga  Geology: Science of processes related to:  Composition, structure, history and life of Earth  Environmental Geology:  Studies entire spectrum of human interactions with the physical environment  It is geology applied to:  Solve conflicts in land use  Minimize environmental degradation  Maximize the benefits of natural resources Earth

Earth History Figure 1.A  Inception: 4.6 Ga  Change over time: Environment and andbioextinction

Fig 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 currently has the right chemical and physical mix needed to support life  No conclusive evidence of life existing elsewhere in the universe has yet been discovered as far as we know  Its size, gravity, magnetic field, water, distance to the Sun, are perfect! Earth is Unique

 Seek to understand all processes that operate on and inside the Earth  Study:  Our planet ’ s long history  Water bodies (rivers and lakes)  Hazardous processes such as earthquakes, volcanic eruptions, flood, and landslides  Rocks/minerals What Do Geologists Do?

Earth Environment (1)  James Hutton (1785): Earth as a superorganism  James Lovelock: Gaia hypothesis Earth is an organism Earth is an organism Life significantly affects the Earth’s environment Life significantly affects the Earth’s environment Life modifies the environment for the betterment of life Life modifies the environment for the betterment of life Life deliberately or consciously controls the global environment Life deliberately or consciously controls the global environment

Earth Environment (2)  Earth: Dynamic, alive, and complex Dynamic, alive, and complex  Everything alive: With a beginning and an end With a beginning and an end  Earth environment as a total, as a whole  Prolong Earth’s sustainable healthy life  Environment monitoring  Environment problems  mapping and analysis  prevention and protection

Environmental Sciences  Environment: A complex system with physical, biological, geological, ecological, and geopolitical aspects  Requires multidisciplinary research: Environmental geology, environmental chemistry, global climate change, biological diversity and ecosystems, environmental economics, environmental ethics, environmental law, etc.  Environmental crisis: Population, environmental hazards, resource limitations and contaminations, environment ownership (both in space and time)

Why environmental geology?  Earth: Source for habitats and resources  There is a geologic aspect in every environmental condition  Environmental geology: Applied geology  To better understand environmental problems  Geologic knowledge for problem solving  Optimize the use of resources to maximize environmental benefits for the society

 Earth Materials (rocks, minerals, soils)  formation, effects on health, as resource or waste  Natural Hazards  floods, landslides, quakes, volcanic eruptions  minimize loss of life  Land for Site Selection  Land use planning, environmental Impact analysis  Hydrologic Processes of surface/ground water  Water resources, pollution  Global Geologic Process  Atmospheric, hydrologic, and lithospheric Environmental Geology Involves Study of:

Landslide is a red flag for future urban development

1. Human Population Growth  Environmental impact = (individual impact X population) 2. Sustainability  This is an objective. Ensure that future generations have equal opportunity to the planet’s resources  Limitation of Resources 3. Concept of Earth having system/subsystems 4. Hazardous Earth Processes 5. Scientific knowledge and values 6. Other concepts:  Uniformitarianism  Our obligation to the future Concepts of Environmental Science

 Pollution (air, water, soil) due to garbage disposal, farming, and fuel burning  Water supplies (Earth population grows by more than 100 M each year). Important for desert cities  Disposal of radioactive waste  Effect of other hazardous waste (chemicals like pesticide) on air, groundwater, and soil  Waste from mining activity (coal, metal ores) Concerns of Environmental Geology

 Geologic hazards (geohazards): Earth processes harmful to humans and their property, e.g., earthquake, volcanic eruption, flooding, slides  Coastline erosion  Sea level rise due to global warming (risk for coastal cities)  Acid rain (due to fuel burning; e.g. S-bearing coal burning)  Ozone depletion; global warming Concerns of Environmental Geology

CO 2 Levels are Increasing

Acid Rain increasing because of burning coal and other fossil fuels

Ozone Depleting because of man made chemicals

Mean Temperature is Rising because of higher CO 2 levels

Figure 1. Grinnell Glacier in Glacier National Park, Montana; photograph by Carl H. Key, USGS, in The glacier has been retreating rapidly since the early 1900's. The arrows point to the former extent of the glacier in 1850, 1937, and The worldwide shrinkage of mountain glaciers is thought to be caused by a combination of a temperature increase from the Little Ice Age, which ended in the latter half of the 19th century, and increased greenhouse-gas emissions.

Sea Level is Rising

P opulation growing exponentially

 The population growth is defined by: P t = P o e rt P t is the population at a given time t P o is the original population r is the growth rate (per time; t -1 or 1/t) t is time (t) e is the base of the natural log (i.e., ln) function (e 1 =2.718)  Unit of P is # (i.e., number of) of people because: (# of people) = (# of people) e (1/t)(t)  The rate (i.e., slope) of growth (i.e., people/time) of the population increases with time (i.e., is not constant)  In simple math the eqn. for exponential growth is: P t /P o =10 0.3n where n is the umber of doubling times Exponential Growth Rate

Year (t) Population (P t )p o =1p t =2 p t =4p t =8 p t =16 Rate of growth  Starting at an arbitrary time, the population is:  2 times (i.e., 2 1 ) as large after each doubling time t D  4 times (i.e., 2 2 ) as large after 2 doubling times, 2t D  8 times (i.e., 2 3 ) as large after 3 t D Population Number of doubling times (t D ) passed 1 = 2 0 = P o 0 2 = 2 1 = P t 1 In general: P t = P o 2 n = P o n 4 = 2 2 = P t 2 where n = t D 8 = 2 3 = P t 3 Given the ratio of P t = P o we can find t D 2 t D = P t n Given P o and doubling time, we can find P t  Exponential growth occurs by an excess of births over death  As the absolute number of people increases, the number of people added each year will increase also, yielding a concave upward 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 growth   Earth’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 (t D ) is a function of growth rate (r): t D =70/r Examples:   If the growth rate r is 0.5%/yr, what is the doubling time (t D ) assuming exponential growth: t D = 70/0.5 = 140 year   If inflation is 8%/yr, how long does it take for the cost of living to double? t D = 70/8 = 9 yr Overpopulation is number one environmental problem!

If the ratio of U.S. population in year 2090 (i.e., P t ) to that of 1850 (i.e., P o ) is 16, find:  How many doubling times have passed (i.e., n)  Duration of each doubling time  % per year increase of the population (i.e., growth rate) P t = P o 2 n = P o n P t /P o = n 16 = n Now take logarithm of both sides: log16 = 0.3n log10(Note: log10 = 1) log2 4 = 0.3n(Note: logx n = nlogx) 4log2 = 0.3n n = 1.2/0.3 = 4 doubling times = 240 years 240/4 = 60 (duration of each doubling time in years) 240/4 = 60 (duration of each doubling time in years) t D = 60 = 70/%r % growth rate = 1.17 (i.e., per year increase) Example 1 - Simple Math

If the population of a country doubles its size each 40 years (i.e., t D = 40), and if the population in 1980 is 10x10 6 heads (i.e., P o ), calculate the:  population in the year 2100 (i.e., P t )  % per year increase of the population (growth rate per year) P t = P o 2 n =P o n P t /P o = n Time period: = 120 years n = 120/40 = 3 P t = P o 2 n = P o 2 3 = P o (3) P t = P o P t = 10x10 6 ( ) log P t = log10 + 6log log 10 log P t = = 7.9 P t = (population in the year 2100) t D = 0.693/r  40 = 70/%  growth rate per year: % = 1.75 Example 2

 Human Population Growth  Rate of growth increased due to better: agriculture, sanitation, medicine, energy sources  Overpopulation  Started few centuries ago  Is a global problem  Population Grows Exponentially Overpopulation

Exponential human population growth Scenario: A student starts a job with 1 cent for the first day. Salary is doubled each day for 31 days! At the end of the month, the student is a multi- 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 ( )   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 Population

World annual population increase peaked in the late 1990s

Uneven growing pace and global distribution  Little access to, or use of, modern family planning methods in less developed countries  Africa: Home to a larger share of world population over next half century  Asia: Many nations overpopulated  India, over one third of its population under 15 years old, is likely the largest population by mid century

Population Bomb: About to Explode? About to Explode?

 Degradation of the environment by pollution  Pollution: Unfavorable alteration of our surroundings, wholly or largely as a by- product of human action  Serious shortages of resources (including food)  Is brought by straining Earth’s ability to provide food, clothing, shelter, and energy  e.g., on the average, each of us, on a yearly basis, uses: 500 kg steel, 25 kg Al, 200 kg salt Effect of Population on Earth Resources

 Development of Geologic Problems  As homes replace fields in flat areas, farming is displaced to hilly regions  Steeper slopes accelerate soil loss, polluting streams with sand and silt  An increased rate of injuries, property damage, and loss of life (due to geologic hazards) Effect of Population on Earth Resources

 Burning petroleum and coal, which increases the greenhouse effect  Intensive farming activities, which have an impact on soil, ground and surface water  Production and release of gases containing chlorine, which destroys ozone  Redistribution of water through the construction of giant reservoirs, which changes the distribution of weight at Earth ’ s surface and alters, slightly but measurably, the rotation of the Earth on its axis Humans are affecting the Earth system:

 Our daily activities are having measurable effects on:  Rainfall  Climate  Air  Water quality  Erosion  Mineral resources  In North America, we use 20 tons of mineral resources per person/year Human Influences …

 Is an environmental objective!  Goal to ensure that future generations have equal access to Earth resources  Is a long-term objective, achieved over decades or centuries  Requires types of development that:  Are economically viable  Do no harm the environment  Are socially just Sustainability

Facts about Sustainability  An evolving concept  Expectation and reality  Criteria variations in space and over time  Long-term implications  Requiring careful resources allocation, large- scale development of new tech for resource use, recycling, and waste disposal

Logging – clear-cut timber harvesting exposes soil, leading to erosion

 Possible for the renewable resources such as air, water, fish, forest, domesticated stock and wildlife, agricultural products  For non-renewable resources, such as fossil fuels and minerals, sustainability is possible by:  Conservation/Recycling to extend their availability  Finding substitution (alternative) for the material Sustainability of Resources

 A system is any portion of the universe that can be isolated from the rest of the universe for observing and measuring change  The simplest kind to understand is an isolated system  the boundary completely prevents the exchange of either matter or energy System Concept

 The nearest thing to an isolated system in the real world is a closed system:  exchanges energy with its surroundings, but not matter  An open system can exchange both energy and matter across its boundary Open and Closed Systems

Systems

 Energy and materials (like water, carbon, and minerals) are transferred from one system to another  To a close approximation, Earth is a closed system because:  Meteorites do come in from space and fall on Earth  A tiny trickle of gases leaves the atmosphere and escapes into space  Earth is comprised of four open systems Earth system

 The atmosphere:  Nitrogen, oxygen, argon, carbon dioxide, and water vapor  The hydrosphere:  Oceans, lakes, streams, underground water, snow, and ice  The biosphere:  All of Earth ’ s organisms, as well as any organic matter not yet decomposed  The geosphere:  The solid Earth from core to surface, composed principally of rock and regolith Our Planet ’ s “ Four Spheres ” or Subsystems (cryosphere is the fifth)

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Earth’s Systems and Changes  Earth: A dynamic system  Two engines behind its dynamics: Internal and external heat sources Internal and external heat sources  Five interconnected subsystems: lithosphere, atmosphere, hydrosphere, and biosphere, cryosphere lithosphere, atmosphere, hydrosphere, and biosphere, cryosphere these subsystems mutually adjust these subsystems mutually adjust

Energy Sources

Short-term changes: Long- lasting adverse effects. Ducktown, TN due to mining, ~ 100 yrs Earth’s Systems and Changes

 Deforestation  Soil erosion  Water and air pollution  Desertification  Pollution due to mining (minerals, coal, oil)  Overuse of groundwater and surface water resources (e.g., Aral Sea) Global Environmental Problems

Dying Aral Sea surrounded by salt flats, due to diversion of water for agriculture

 The whole Earth behaves like an organism  It is a self-regulating network of interdependent physical and biological systems  A disturbance (e.g., deforestation) in one part of the system (Earth) must result in adjustment in other parts (e.g., global warming) System Approach

Earth’s Systems and Changes (2)  System conditions: Open vs. closed systems  System input-output analysis  System changes: Types of changes, rates of changes, scales of changes, etc.  Rates of change: Average residence time  T = S/F (T: residence time, S: total size of stock, F: average rate of transfer)

1. Earth:  rocks and minerals  origin, variety, distribution, and pollution of soil  causes of, distribution, and prediction of earthquake/volcanic activity  cause and prevention of coastal erosion and slope failure  mineral and water resources Environment influenced by three inter-related variables

2. Air:  composition and circulation  pollution by human activities  climate Environment influenced by three inter-related variables

3. Water:  distribution  movement and flooding  range in chemical composition  pollution by human activities  management Environment influenced by three inter-related variables

H 2 O circulates freely among the:  atmosphere (as gas, e.g., vapor)  ground surface (as solid, e.g., ice, and liquid water)  subsurface (liquid water) Solid surface material are:  carried to the ocean by runoff (as suspended, dissolved, and bed loads)  carried to the atmosphere by wind (as dust) Inter-relationship of atmosphere, hydrosphere, & lithosphere

 The movement of materials is continuous  There are two key aspects to cycles:  The reservoirs in which the materials reside  The flows, or fluxes, of materials from reservoir to reservoir  The speed of movement differs greatly in different cycles Cyclical Movements

 The hydrologic cycle  Water in Earth ’ s hydrosphere  The rock cycle  Rock is formed, modified, decomposed, and reformed by the internal and external processes of Earth  The tectonic cycle  Movements of plates of lithosphere, and the internal processes of Earth ’ s deep interior that drive plate motions Three Most Important Cycles

 Is powered by heat from the sun  Encompasses the movement of water in the atmosphere, in the hydrosphere, on the Earth ’ s surface, and in the Earth ’ s crust The hydrologic cycle

 Rock is any naturally formed, nonliving, firm and coherent aggregate of mineral matter that constitutes part of a planet.  The three rock families:  Igneous rock:  Created through the cooling and solidification of magma  Sedimentary rock:  Formed from deposits of sediment  Metamorphic rock:  Formed by the effects of pressure and heat on existing rocks Rock Cycle

 Tectonics is the study of the movement and deformation of the lithosphere  When magma rises from deep in the mantle, it forms new oceanic crust at mid ocean ridges  The lifetime of oceanic crust is shorter than the lifetime of continental crust  The most ancient oceanic crust of the ocean basins is only about 180 million years old, and the average age of all oceanic crust is about 70 million years old Tectonic Cycle

 When all oceanic crust sinks back into the mantle, it carries some water with it  The water is driven off during volcanic eruptions  Some constituents in the hot rock (calcium, magnesium) are the same as those of seawater Tectonic Cycle

 The other cycles include the biogeochemical cycles:  Carbon  Oxygen  Nitrogen Other cycles

CO 2 Cycle

Predicting Future Changes  Uniformitarianism  The present is the key to the past  The present is the key to the future  Changes of frequency and magnitude: Geological processes and human activities  Environmental unity: Chain of actions and reactions  Earth system  Gaia hypothesis: Earth is a living organism  Complex and interrelated subsystems  Global perspective on environment

Hazardous Earth Processes Hazardous Earth processes and risk statistics for the past two decades  Annual loss of life: About 150,000  Financial loss: > $20 billion  More life loss from a major natural disaster in a developing country (2003 Iran quake, ~300,000 people)  More property damage occurs in a more developed country

Risk Assessment  Hazard identification  Risk assessment (types, probability, and consequences of impact)  Critical facility mapping and analysis  Economic impact analysis  Societal impact analysis  Total environmental impact analysis  Risk management and mitigation

Risk Perception  Public attitude toward risks  Public acceptance for risks  Threshold for living with dangers  Planning decisions, e.g., floodplain development, waste disposal  Public awareness and collective actions  Anticipatory measures  Mitigation planning

Scientific Knowledge and Values (2)  3-D environmental problems  Changes of environment in the 4-D (time)  Expansiveness of geologic time  Broad spectrum of geologic processes  Great variations in rates of geologic processes  Humans are super agent of change  Holocene epoch  Industrialization and global environmental changes

Scientific Knowledge and Values (1) Figure 1.12

Science and Solution  Science: Accumulated knowledge  Knowledge: Basis for decision making  Scientific methods: Formulate possible solutions to environmental problems  Scientific design: Structure more suitable for certain environmental settings  Scientific info: Public awareness and environmental regulations

Applied and Critical Thinking Topics  Do you think the Earth is a living organism? Why or why not?  Why did you take this environmental geology course?  Would an exponential negative growth of human population be a solution to many environmental problems?  Science can certainly provide solutions to environmental problems, but think of ways that science brought about environmental problems.