The Costs & Benefits of

MINERAL RESOURCES

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 Value • Direct value – Raw, recycles – Import, export • Indirect value – Processes • Value added – E.g., agriculture

Common Use of Mineral Products NON-METALLIC METALLIC HYDROCARBON

Mineral Resources and Reserves

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

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 falls B. Reserves fall, resource constant C. Reserves constant, resource falls D. Reserves rise, resource falls E. 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)

Impact of Mineral Extraction and Processing (1)

General 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: Increased demands for housing and services

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 Extraction and 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 – Clean Air Act • Land reclamation genetic engineering  developing countries • Environmental Regulations – Forbid bad mining practices – on- and offsite treatment of wastes – ~50% of land used in mining industry reclaimed • Use of new biotechnology in mining – Bio-oxidation, bioleaching, bio-absorption,

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

Recycling Mineral Resources (2) • 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 (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?