Mineral resources

Resources• Reserves – Natural resources that have been discovered discovered && – Deposits that we know or believe to exist, but that are not exploitable today because of technologic

Energy Resources

• Uranium (U) – used for nuclear power

• Has a Minimum Concentration Factor > 1000

• Source Rock – Igneous

• U is leached (dissolved) into groundwater

Hydroelectric and

Tidal Power

• Movement of water

drives turbines

• Dams – gravity key force

• Tidal – tidal force, need a tidal range of > 8 m

(nearly impractical)

• Hot groundwater drives

turbines

Mineral Resources

Daily Questions

• Within your groups, identify one task you all have completed today Collectively

think about the task and brainstorm

Produce a list of all of the mineral resources that were used in that task.

Some Important Minerals and there Uses

• Galena [PbS] – source of lead – car batteries

• Magnetite, Hematite [FexOy] – iron ore

• Bauxite [Al2O3*2H2O] – aluminum ore

• Chalcopyrite [CuFeS2] – copper ore

• Quartz [SiO2] – glass and electronic components

• Gypsum [CaSO4*2H2O] – sheetrock, plater of paris

• Sphalerite [ZnS] – zinc ore

• Calcite [CaCO3] – portland cement, soil conditioner, antacids

• Garnet [Al2(SiO4)3+other metals] – abrasives

• Olivine [(Fe,Mg)2SiO4] – silicon chips for computers

• Sulfur [S] – insecticides, rubber tires, paints, papermaking, etc.

• Halite [NaCl] – Table salt

• Graphite [C] – lubricant, pencil lead

• Feldspars [K,Ca,Na,Al, silicates] – porcelain, source of K

• Any other element that is not a major component of a mineral

• Gold [Au], Silver [Ag], Platinum [Pt], Titanium [ Ti], Tin [Sn], etc.

Reserves vs Resources

• Reserves

– Natural resources that

have been discovered discovered &&

– Deposits that we know

or believe to exist, but that are not exploitable today because of

technological, economical, or political reasons

– Oil – 2 trillion barrels

Nonrecoverable resources (present in the earth but not obtainable

with present technology)

Recoverable resources (not likely to be economic

in foreseeable future)

Unconceived Resources

Hypothetical, speculative,

or inferred resources

Technological Threshold

Potential Economical Threshold

Proven Resources Discovered Undiscovered

• Elements comprise > 0.1% (by

weight) of the crust

• Form as principal component

in minerals within common

rocks – i.e iron (Fe) Fe2O3

• Form very large deposits

• Form rock deposits

Geochemically Abundant Elements (GAE)

Geochemically Scarce Elements

substitute in rock forming minerals

• Form small deposits

• Ore minerals include sulfides, native elements, etc

Will run out

Abundant

Mineral Deposits

• Elements need to be concentrated

• Minimum Grade - minimum amount of element necessary to economically mine element

• Minimum Concentration Factor (MCF) –

Minimum Grade divided by the Crustal

Abundance

– GAE have MCF < 100

– GSE have MCF > 100

Comparison of Concentrations of Elements in the Earth’s Crust with Concentrations needed to operate

a Commercial Mine

Concentration in Crust (% by Weight)

Concentration Required

to Operate a commercial mine (% by Weight)

Enrichment Factor

Process that concentrate elements

• Magmas heat up the water

• Water flows into fractures,

faults, joints, etc where it

cools and precipitates

(deposits) the metals

Hydrothermal Processes

Magmatic Processes

• Gravity Settling

– Dense, early-crystallizing

minerals sink to the bottom

of the magma chamber

• Filter Pressing

– Tectonic force compress a

magma chamber and force

the still-liquid portion into

fractures, creating large

crystals

• These processes have

produced large bodies of

iron, chromium, titanium,

and nickel

elements are heavy

and are deposited

Placer Gold

• Alteration of rock

concentrates the

elements

• The heat and

pressure force out

the GSE

(“impurities”)

• Chemical weathering removes soluble material.

• Ore material (elements of

interest) are left behind in a

concentrated residue.

Weathering

Ore Mineral

• Ability to separate and readily process the metal (element) from the ore material.

• Need to look at

– The energy to process the material

– The cost to process the material

– The value of the metal

• Basically, is it profitable to mine the metal?

Mineralogical Barrier

• Increase in energy and cost associated with

the production of GSE

Energy and Cost

Metals trapped in minerals (silicates)

Metals the have been concentrated

Ways to overcome the mineralogical barrier

• Improve technology

• Recycle

• Come up with cheap energy to break silicate bonds

Daily Assignment

Place the following on the Venn Diagram

1.Gold2.Oil3.Coal4.Iron5.Copper6.Gravel

1

5

2, 3, 6 4

Plate Tectonics and Resources