The Costs & Benefits of MINERAL RESOURCES. Backbone of modern societies Availability = a measure...

The Costs & Benefits of

MINERAL RESOURCES

• Backbone of modern societies• Availability = a measure of a society’s wealth• Important in people’s daily life as well as in

overall economy• Processed materials from minerals account for 5%

of the U.S. GDP• Mineral resources are nonrenewable

Mineral Resources

Mineral Value

• Direct value– Raw, recycles

– Import, export

• Indirect value– Processes

• Value added– E.g., agriculture

Common Use of Mineral Products

METALLIC

HYDROCARBON

NON-METALLIC

Mineral Resources and Reserves

• Defining factors– Geology, technology, economy, and legality

Resource = Usable economic commodity extracted from naturally formed material (elements, compounds, minerals, or rocks)

Reserve = Portion of a resource that is identified and currently available to be extracted legally and profitably

Resources and Reserves

• Political football (e.g., Montana coal)• Consider the effects on US R&R of the

recent fall in crude oil price:A. Reserves fall, resource fallsB. Reserves fall, resource constantC. Reserves constant, resource fallsD. Reserves rise, resource fallsE. Reserves rise, resource constant

Mineral Resources Problems

• Nonrenewable resources– Finite amount of mineral resources and growing

demands for the resources

• Supply shortage due to global industrialization– More developed countries consuming

disproportionate share of mineral resources

• Erratic distribution of the resources and uneven consumption of the resources. – Highly developed countries use most of the

resources; supply varies

Major Import Sources (Table 14.2)

• Friends– Canada: Metals

– United Kingdom: platinum, rare earths

• Other– China: graphite, tin, tungsten…

– South Africa : platinum, fluorspar

– Chile: arsenic, iodine

Responses to Limited Availability

• Find more sources

• Find a substitute

• Recycle

• Use less and make more efficient use of what is available

• Do without

Geology of Mineral Resources

• Metallic ore – Useful metallic minerals that can be mined for a profit– Technology, economics, and politics

• Concentration factor– Concentration necessary for profitable

mining, e.g., for gold is about 5000• Variable with types of metals

• Variable over time

Genesis of Mineral Resources

Plate Tectonics and Mineral Resources

• Plate boundaries– related to the origins of many ore deposits

• Plate tectonic processes– high temperature & pressure– partial melting – promote release and enrichment of metals

along plate boundaries• Common metal ores at plate boundaries

– Fe, Au, Cu, and Hg, etc.

Example: Mid-ocean ridge

• Circulation of sea water– Salty and metallic

• Heated, then cooled– Precipitates ores

• Can we mine MOR deposits?

• What happens at subduction zones?

What explains Urals, S. Africa?

Intrusive Igneous Deposits (Silverton)

• Major source of metals and mineral wealth

Mineral Resources and Environmental Impact

• Environmental impact– From mineral exploration and testing

– From mineral mining

– From mineral resources refining

– From mining waste disposal

Environment Impact of Mineral Development

• The impact depends upon many factors:– Mining procedures

– Hydrologic conditions

– Climate factors

– Types of rocks and soils

– Topography

• Also population: NIMBY

Impact of Mineral Exploration and Testing

• Mineral exploration and testing– Surface mapping, geochemical, geophysical,

and remote-sensing data collection

– Test drilling

• Impact– Generally minimal impact

– More planning and care needed for sensitive areas (arid, wetlands, and permafrost areas)

General impactGeneral impact

• Direct impact on land, water, air, and biological environment

• Indirect impact on the environment: Topographic effect, transportation of materials, etc.

• Impact on social environment:Impact on social environment: Increased demands for housing and services

Impact of Mineral Extractionand Processing (1)

Impact of Mineral Extraction

& Processing• Impact from mining

operations– Land disturbances– Waste from mines: 40% of

the mining area for waste disposal, mining waste 40% of all solid wastes

– Special mining, e.g., chemical leaching from gold mining

– Mining acid drainage, during mining and post-mining

Impact of Mineral Extractionand Processing (4)

• Water pollution– Trace elements leach

into water• Cd, Co, Cu, Pb, Mo, Zn

– Flooding of abandoned mines• oxidation of sulfide ores

= sulfuric acid

– Acid mine drainage from tailings

Minimizing the Impact of Mining (1)

• Knowledge and technology transfer– developed countries developing countries

• Environmental Regulations– Forbid bad mining practices– Clean Air Act– on- and offsite treatment of wastes

• Land reclamation– ~50% of land used in mining industry reclaimed

• Use of new biotechnology in mining– Bio-oxidation, bioleaching, bio-absorption,

genetic engineering

Minimizing the Impact of Mining (2)

Recycling Mineral Resources (1)

• Why recycle? Consider the impact of the wastes– Toxic to humans

– Dangerous to natural ecosystems

– Degradation of air, water, and soil

– Use of land for disposal

– Aesthetically undesirable

• Waste contains recyclable materials • Saves energy, money, land, raw mineral

resources from more mining• Saves energy and money when recycling

instead of refining raw ore materials• Recycling has been proven to be

profitable and workable

Recycling Mineral Resources (2)

Recycling Mineral Resources (3)

• Most-recycled metals- Iron and steel, 90% by weight- Producing steel from recycled scrap

o 1/3 as much energy needed to as from original ore

• More than $40 billion produced from recycled metals in 1998

• Other recycled metals- Lead (63%)- Aluminum (38%)- Copper (36%)

Minerals and Sustainability

• Sustainability: long-term strategy for consuming the resources

• Find an alternative material for the metal• glass fiber cable for copper wires

• Use raw materials more efficiently• More Research & Development

• Innovative substitutes• Ways to maintain the Resource:Consumption• A solution to the depletion of nonrenewable

resources

Questions…

1. Considering the fact that mineral resources are nonrenewable:a) Do you believe that technology will eventually

help to meet the growing demand for mineral resources?

b) If yes, explain.2. Biotechnology shows the potential for cleaner

minerals extraction and waste disposal. a) Could biotechnology bring about any

environmental problems?3. What types of environmental impact would occur if

we increasingly extract more mineral resources from the seafloor?