Transcript Mineral Resources and Environment

Mineral Resources and Environment
Mineral Resources – elements, compounds, minerals, or rocks concentrated
in a form that can be extracted to obtain a usable commodity
Reserves – that portion of a resource that is identified and currently
available (i.e. from which usable materials can be legally and economically
extracted at the time of evaluation).
Minerals and Human Use
Categories:
1. Metal Production
& Technology
2. Building Materials
3. Minerals for
Chemical Industry
4. Minerals for
Agriculture
Mineral Products in a Typical Home
Building materials
Sand, gravel, stone, brick (clay), cement, steel, aluminum,
asphalt, glass
Plumbing and wiring materials
Iron and steel, copper, brass, lead, cement, asbestos, glass,
tile, plastic
Insulating materials
Rock, wool, fiberglass, gypsum
Paint and wallpaper
Mineral pigments (such as iron, zinc, and titanium) and fillers
(talc and asbestos)
Plastic floor tiles, other plastics
Mineral fillers and pigments, petroleum products
Appliances
Iron, copper, and many rare metals
Furniture
Synthetic fibers from coal and petroleum ; steel springs; wood
Clothing
Natural fibers grown with mineral fertilizers; synthetic fibers
Food
Grown with mineral fertilizers; processed and packaged
Drugs and cosmetics
Mineral chemicals
Other items
Windows, screens, light bulbs, porcelain fixtures, china,
utensils, jewelry: all made from mineral resources
Mineral Depletion Curves
Basic problem w/ availability of resources is not exhaustion, but cost of maintaining
adequate reserves. At some pt., cost of mining exceeds value of the resource.
Options: find more, find a substitute, recycle/reuse what we have, use less and
increase efficiency of use, do without
Choice depends on: Economics, Social factors, Environmental factors
Hypothetical Depletion
Curves:
1. Rapid consumption--the
most common pattern except
for precious metals (PGM)
2. Consumption with
conservation
3. Consumption, conservation,
and recycling
U.S. per Capita
Consumption
Rates of Use
Fe and Na--very high,
about 1 billion tpy
N,S,K, and Ca-mod
high as fertilizers--10
to 100 mtpy
Zn, Cu, Al, and Pb--3
to 10 mtpy
Au and Ag about
10,000 tpy
•
•
•
•
•
•
•
•
•
•
•
Crushed Stone
Sand and gravel
Salt
Gypsum
Phosphate
Potash
Iron
Aluminum
Zinc
Lead
Copper
•
•
•
•
•
•
•
•
•
•
•
4.6 tons
3.2 tons
396 pds
206 pds
374 pds
48 pds
570 pds
48 pds
11 pds
11 pds
20 pds
Reliance on Imports
Arsenic
Bauxite
100%
100%
Chile, France, Mexico
Australia, Guinea, Jamaica
Columbium
Graphite
Manganese
100%
100%
100%
Brazil, Canada, Germany
Mexico, China, Brazil
S. Africa, France, Gabon
Mica
Strontium
Thallium
Gems
100%
100%
100%
98%
India, Belgium, Brazil
Mexico, Spain, Germany
Belgium, Japan, UK
Israel, Belgium, India
Platinum
94%
S. Africa, UK, FSU
Geology of Mineral Resources
•
•
•
Aspects and processes of the geologic
cycle are responsible for producing local
concentrations of minerals
Genesis of Common Mineral Resources
– Plate tectonics and minerals
– Mobilization of elements at
convergent boundaries due to partial
melting (Hg in volcanic rocks)
Concentration
– Ore = rock body containing valuable
elements/metals that can be
extracted
– Concentration factor = ratio of
necessary concentration (in ore) for
profitable mining to average
concentration in Earth’s crust
Plate Tectonics and Minerals
•Plate boundaries are related to origin of iron, gold, copper, and mercury ore deposits
•Metallic ore deposits & divergent plate boundaries: circulation of water through
fractured, basaltic rock concentrates metallic sulfides as precipitates
•Convergent plate boundaries concentrate metallic ores through partial melting of
oceanic lithosphere at a subduction zone – high P & T releases metals from melts,
concentrating them.
Mercury Deposits Example
Geology of Mineral Resources
•Igneous processes
–Kimberlite – diamond xtals in coarse
grained igneous rock, originally formed at
high P (deep) and have been moved to
surface
–Crystal settling
–Late magmatic
–Hydrothermal (hot water) ore deposits
•Metamorphic processes
–Contact metamorphism
–Regional metamorphism
Geology of Mineral Resources
•
–
•
•
–
•
•
•
–
–
–
–
Sedimentary processes
Processes
Transport
Separation by size, shape, and density
Materials
Sand and gravel-old rivers, beaches, and
glacial deposit
Placer deposits-gold and diamonds;
separated by density from running water
and on beaches
Evaporites--seas that are separated or in
internal drainage basins
Marine (K and Na, gyp, anhydrite)
Non-marine (CO3, sulfates, borate,
nitrate, I, and Br)
Brines (Br, I, CaCl2, Mg)
Salt domes--for salt, sulfur, and oil;
potential sites for radioactive waste