Transcript Earth Resources

Mineral Resources
Resource Use
• U.S. has 5% of World Population
• U.S. Consumes 1/4 of World Resources
But
• U.S. Produces 1/4 of Global GDP
But
• Much of our GNP is consumed internally
Mineral Resources
• Building
• Metallic Minerals
Stone, Sand, Gravel,
– Non-ferrous: Copper,
Limestone
Zinc, Tin, Lead, Aluminum,
Titanium, Manganese,
• Non-metallic Minerals
Magnesium, Mercury,
Sulfur, Gypsum, Coal,
Vanadium, Molybdenum,
Barite, Salt, Clay,
Tungsten, Silver, Gold,
Feldspar, Gem Minerals,
Platinum
Abrasives, Borax, Lime,
• Energy Resources
Magnesia, Potash,
Phosphates, Silica,
– Fossil Fuels: Coal, Oil,
Fluorite, Asbestos, Mica
Natural Gas
• Metallic Minerals
– Uranium
– Ferrous: Iron and Steel,
– Geothermal Energy
Cobalt, Nickel
Three Emerging Resource Problems
• Lithium (Batteries)
– Evaporites (Bolivia)
– Pegmatites (Lepidolite, Spodumene)
• Rare Earths (Electronics)
– Col-Tan and Congo Civil War
– Chinese Monopoly
– California mine to reopen
• Phosphorus (Fertilizer)
– Morocco, China, South Africa, Jordan, U.S. = 90%
The Elements
Types of Ore Deposits
Magmatic
• Pt, Cr, Fe, Ni, Ti, Diamond
Pegmatite
• Li, Be, U, Rare Earths,
Feldspar, Mica, Gems
Hydrothermal
• 600 C: W, Sn
• 400 C: Au, U, Ag, Co, Mo
• 200 C: Cu, Zn, Cd, Pb
• Cool: Hg, As
Sedimentary Rocks
• Fe, Cu, U, Mn, Mg
Weathering
• Secondary Enrichment:
– Cu, Ni
• Soils
– Al, Ni
• Evaporites
Placer
• Pt, Au, Sn, Ti, W, Th, Rare
Earths U (Fossil), Gems
Concentration Factors and
Economics
• Natural Abundance
• Geologic Processes to Concentrate Element
– Most involve water
• Intrinsic Value of Material
• Cost of Extraction from Earth
– Gold versus Gravel
Prospecting and Exploration
What we’re looking for is
subtle.
Satellite and Aerial
Photography
Remote Sensing
Geological Mapping
Magnetic Mapping
Gravity Mapping
Radioactivity Mapping
Geochemical Sampling
Electrical Sounding
Ground-Penetrating
Radar
Seismic Methods
– Reflection - Detailed
but Expensive
– Refraction - Cheap but
Not Detailed
Core Sampling and Well
Logging
Drill Core
Geologic
Map of
Wisconsin
Gravity
Map of
Wisconsin
Magnetic
Map of
Wisconsin
Satellite
Image of
Wisconsin
Economic Factors in Mining
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Richness of Ore
Quantity of Ore
Cost of Initial Development
Equipment, Excavation, Purchase of Rights
Operating Costs: Wages, Taxes, Maintenance,
Utilities, Regulation
• Price of the Product
• Will Price Go up or down?
Life Cycle of a Mine
• Exploration
• Development
• Active Mining
– Excavation
– Crushing, Milling, Flotation, Chemical
Separation
– Smelting and Refining
– Disposal of Waste (Tailings)
• Shut-down
Issues in Mineral Exploitation
Who Owns (Or Should Own) Minerals?
• Landowner,
• Discoverer,
• Government
Unclaimed Areas:
• Sea Floor,
• Antarctica
Who Controls Access for Exploration?
• Remote Sensing vs Privacy
Problems of Mining
Safety
• Mine Wastes
• Pollution
• Dust
• Noise
Economic Impact
• "Boom and Bust"
Cycles
Environmental
Problems
• Exploration
• Construction and
Operation
• Waste Disposal
• Sulfur (H2 SO4 )
Sulfur
• Present in sulfide ores, pyrite or organic
sulfur in coal, organic sulfur in petroleum
• Smelting or burning create SO2
• 2SO2 + O2  2SO3
• H2 O + SO3  H2 SO4
Sulfuric Acid
• Contributor to Acid Rain
– Neutralized by carbonates and mafic igneous
rocks
– Worst in granitic bedrock
• Weakens tailings piles, slopes, dams
• Acidifies surface water
• Contributes to dissolved metals