180 likes | 324 Views
Environmental Geology. Prof. Steven Dutch Office: LS 463 Phone: 465-2246 Email: dutchs@uwgb.edu Home Page: www.uwgb.edu/dutchs. Minerals. Toxins Hg, Cd, As, etc. Carcinogens Asbestos, Silica Sand Radiological hazards Uranium and Thorium decay series (U, Th, Ra, Rn, Po)
E N D
Environmental Geology Prof. Steven Dutch Office: LS 463 Phone: 465-2246 Email: dutchs@uwgb.edu Home Page: www.uwgb.edu/dutchs
Minerals • Toxins • Hg, Cd, As, etc. • Carcinogens • Asbestos, Silica Sand • Radiological hazards • Uranium and Thorium decay series (U, Th, Ra, Rn, Po) • Hazards arise from: • Bulk Chemistry • Trace impurities • Physical State
Igneous Rocks and Volcanoes • Direct volcanic hazards • Lava Flows • Ash falls • Pyroclastic flows • Mudflows • Landslides and cone collapse • Floods • Gases • Climatic effects • Stratospheric ash • Sulfur aerosols • Super-Volcanoes • Magma chamber collapse • Flood basalts
Surface Water • Lack of potable water is the single greatest hazard to human health • Women in arid developing regions spend up to 1/3 of their time gathering water • Diarrhea from contaminated water is the single greatest cause of infant mortality. • Aid workers have to fight to convince mothers that diarrhea is not a normal childhood disease • Problems with surface water • Disease organisms • Contamination by pollutants and sewage • Overuse of Surface Water • "Whiskey's for drinking, water's for fighting over." • Owens Valley, California • Aral Sea
Mechanics of ground water Recharge zone Aquifers Aquitards Springs, wetlands and lakes Artesian systems Wells Karst Human impacts on ground water Cone of depression Migration of salt water and contaminants Contamination of aquifers Land subsidence Impact on surface water Ground Water
No soil, no food. It's that simple. Soils are complex entities, resulting from the interaction of: Time Climate Vegetation Drainage Types of Soils Soil Erosion Poor plowing practices Overgrazing Deforestation Other Soil Degradation Climatically inappropriate farming Urbanization Soil preservation approaches Contour plowing Strip cropping No-till agriculture Reforestation Soils
Weathering and Erosion • Floods • River floods • Coastal floods • Dam Failure (Natural or Artificial) • Mass Wasting • Soil Creep • Mudflows • Avalanches • Slumps
Deserts and Wind Erosion • Desertification • Expansion of deserts at the margins due to overgrazing and deforestation • "The Bedouin is not the son of the desert, but its father." • North Africa was forested in pre-Roman times • Sub-Saharan Africa • Wind Erosion • Loess soils feed the world • Present-day wind erosion strips topsoil • Burial of vegetation or exposure of roots • Respiratory hazards • Cost of clearing wind-blown sediment from roads
Coastal Processes • Storm Surges • Galveston, 1900 • Bangladesh, 1971 • New Orleans, 2005 • Subsidence • Louisiana • Erosion • Effects on property values • Attempts to control
Causes Plate boundaries Intraplate Hazards “Earthquakes don’t kill people, Buildings kill people” Tsunami Landslide Fire Hazard Mitigation Construction Zoning Prediction? Short Term (Precursors) Long Term (Seismic Gaps, Paleoseismology) Earthquakes
Mineral Resources Metallic versus non-metallic Extraction methods Environmental Impacts Non-Petroleum energy resources Coal Uranium Geothermal Petroleum and Natural Gas Geopolitical and Geological realities Petroleum production Non-conventional energy sources Methane hydrates Tar sands Oil shales Oil mining Hot dry rock geothermal Deep Earth gas hypothesis Resources
Can we predict impacts? The Torino Scale of Impact Hazard Named for the city in Italy, not a person Assesses both probability of event and potential effects of impact Therefore not completely consistent. Likely impact scenarios Atmospheric impact and air burst (Tunguska, 1908) Surface impact causing local damage Surface impact with 100 km damage radius Surface impact with 1000 km damage radius Surface impact with global effects What happens during impact Environmental Effects Radiant heat and flash burns Blast wave Seismic waves Tsunami Ejecta Stratospheric dust Liberated volatiles (carbon dioxide, sulfur, methane) Impact volcanism - a myth Extraterrestrial Hazards
Military Impacts on the Environment • Clausewitz: "War is policy carried on by other means." • All war is inherently political • The last general who was utterly unconstrained was Napoleon • Incidental (collateral) damage • Modifications to facilitate own operations • Modifications to impede enemy • Strategic Modifications • Environmental Terrorism
Exponential Growth • Invest one cent at 1% interest per year, compounded annually, in the year 1 AD • By now it would be worth $.01 x (1.01)2011 = $4,900,000.00 • At 2%: $1,895,592,883,959,335.15 or 30 times the total GDP of the earth • At $1000 per ounce = 58,952,939 tons of gold. • Total amount of gold ever mined is around 150,000 tons. You could not be paid in gold.
Exponential Growth • Doubling time = 72 years / % annual growth rate • 4% = 18 years • 3% = 24 years • 2% = 36 years • 1% = 72 years • Implications for Earth • All exponential growth, no matter how low the rate, eventually becomes huge. • You can't get an infinite amount of anything (like people) into a finite space • You can't get an infinite amount of anything (like resources) out of a finite space • Nothing can grow forever
Exponential Growth • At 2% per year, global population will be: • 12 billion in 2041 • 24 billion in 2077 • 48 billion in 2113 • One person per square meter (land and sea) in 2594 • Equal to the mass of the earth in 3596 • What will limit growth? • Natural methods (famine, disease and war) • Imposed by society (China's one-child policy) • Personal preference (Demographic Transition) • No amount of environmental awareness will matter unless population growth stops
Exponential Growth • Impacts on Earth • Diversion of primary capacity to feed humans (now at least 25%) • Destruction and fragmentation of habitat • Direct consumption of animals and plants for food and fuel • Increased degradation of land by erosion • Increased hazard to humans as populations in dangerous terrain increase • Prognosis • Humans will probably always operate in crisis management mode (not dealing with a problem always offers immediate returns) • Sooner or later we will miscalculate our ability to avert disaster
One Last Demographic Effect of Population Growth Population Equals Regulation