copyright (c) 2005 pearson education canada, inc.21-1 powerpoint presentation stan hatfield....

Copyright (c) 2005 Pearson Education Canada, Inc. 21-1

PowerPoint PresentationStan Hatfield . Southwestern Illinois College

Ken Pinzke . Southwestern Illinois College

Charles Henderson . University of Calgary

Chapter 21

Mineral and Energy Resources

Copyright (c) 2005 Pearson Education Canada Inc. 21-2

Renewable and Nonrenewable Resources

Mineral resources• Canada has a rich supply, but no nation is

completely self sufficient


Canadian Per Capita Consumption of Selected Mineral Resources



Renewable resources• Resource can be replenished over

relatively short time spans • Examples include

– Plants

– Animals for food

– Trees for lumber– Energy from flowing water, sun, wind



Nonrenewable resources • Significant deposits take millions of years

to form; from a human perspective there are fixed quantities

• Examples– Fuels (coal, oil, natural gas)– Metals (iron, copper, uranium, gold)

Some resources, such as groundwater, can be placed in either category depending on how they are used


Metallic Mineral Deposits and Geologic Processes

Mineral deposits may be found in a variety of plate tectonic settings.

Mineral resources include reserves = identified deposits from which minerals can be extracted profitably now or in the future with technological advances.


Mineral resources• Ore – refers to useful metallic minerals that

can be mined at a profit and, in common usage, to some nonmetallic minerals such as fluorite and sulphur

• To be considered of value, an element must be concentrated above the level of its average crustal abundance

• Most nonmetallic minerals are generally not called ores, but rather they are called industrial minerals



Magmatic Deposits • Some of the most important accumulations

of metals are associated with magma that forms igneous rocks

• Certain metals are enriched in certain magmas and further concentrated during cooling of the magma



Magmatic Deposits: Gravitational Settling

– heavy minerals that crystallize early, settle and concentrate on the bottom of the magma chamber

High-density minerals sink to the bottom of the magma

chamber.



Magmatic Deposits: Immiscibility– Separation and non-mixing of liquid phases

of a magma (e.g., Sudbury, Ontario and Voisey’s Bay, Newfoundland and Labrador)

– Nickel deposits of Sudbury and Voisey’s Bay have similar origins, but different triggering mechanisms

A sample of nickel-bearing rock from Sudbury.



Magmatic Deposits: Pegmatites– Melt remaining in last stages of cooling is rich

in volatiles and rare elements

– Such a melt is very fluid and invades cracks and results in large crystals

Pegmatites, like these dykes from Ontario, are felsic composition rocks that are mined for uranium, thorium,

beryllium, lithium, tantalum, niobium, feldspar, muscovite…




Hydrothermal Deposits• Hydrothermal Deposits associated with

Igneous Activity– Among the best known and important ore

deposits, generated from hot-water solutions – Majority originate from hot, metal-rich fluids

that are remnants of late-stage magmatic processes

– Move along fractures, cool, and precipitate the metallic ions to produce vein deposits




Igneous Activity– Can occur as disseminated deposits, which are

distributed throughout the rock body, rather than concentrated in veins; called porphyry deposits = (low grade; large volume)




Igneous Activity– Volcanogenic Massive Sulphide (VMS)

deposits are pod-shaped bodies composed entirely of interlocking sulphide minerals

– Heated seawater, rich in dissolved metals gushing from seafloor as black smokers today, may have produced VMS deposits in ancient rocks


Hydrothermal Deposits at Black Smokers


Pegmatite and Hydrothermal Disseminated Deposits



Sediment-Associated Hydrothermal Deposits• Sedimentary Exhalative (SEDEX) Deposits

– SEDEX deposits are thin layers of massive sulphide interbedded with sedimentary rocks (e.g., Sullivan Mine, British Columbia)

SEDEX deposits typically occur in the sediment fills

of rift basins.



Sediment-Associated Hydrothermal Deposits• Sedimentary-Hosted Stratiform Deposits

– Copper-bearing brines moving through coarse-grained sedimentary rock are forced upward through oxygen-poor, sulphide-rich mud, which promotes precipitation of minerals

• Mississippi Valley-type Deposits– Metal-bearing brines migrate toward basin edge

and react with limestone



Sedimentary Deposits• Banded Iron Formations

– Reducing conditions for much of the early Precambrian resulted in large quantities of ferrous iron in solution

– At some point, photosynthesizing bacteria (cyanobacteria) generated sufficient oxygen to precipitate insoluble iron oxide minerals

– Form very important source of iron-ore on many continents including in the Lake Superior region



Sedimentary Deposits • Placer deposits – formed when heavy

metals are mechanically concentrated by currents

• Examples include – Gold, Platinum, Diamonds


Klondike Gold Rush: placer miners with sluice box in 1901 (right) and modern gold

mining on same creek in 2002 (left)



Deposits Associated with Metamorphism • Many of the most important metamorphic

ore deposits are produced by contact metamorphism

– Sphalerite (zinc)

– Galena (lead)

– Chalcopyrite (copper)


Skarns are Associated with Contact Metamorphism



Deposits Associated with Weathering • Secondary enrichment – concentrating

metals into economically valuable concentrations

• Bauxite– Principal ore of aluminum

– Forms in rainy tropical climates from chemical weathering and the removal of undesirable elements by leaching


Bauxite – the principal ore of aluminum



Deposits Associated with Weathering• Other deposits, such as many copper and

silver deposits, result when weathering concentrates metals that are deposited through a low-grade primary ore


Nonmetallic Resources

Nonmetallic mineral resources • Use of the word “mineral” is very broad • Two common groups

– Aggregate and Stone

– Natural aggregate (crushed stone, sand, and gravel; latter two associated with glacial outwash deposits throughout Canada)


Significant Industrial Mineral Deposits in Canada.



Industrial Minerals• Diamonds

– Most diamonds are found in unique ultramafic igneous rocks called kimberlites

– Magma generated by partial melting of asthenosphere below 150 kilometres and then rises quickly to the surface, picking up diamonds from solid lithospheric mantle


Kimberlite Pipes and Diamonds



Other Industrial Minerals• Clays • Carbonate Minerals• Evaporite Salts (potash very important

resource in Devonian of Saskatchewan)• Phosphate (Permian Phosphoria

Formation in Idaho, USA)• Sulphur


Nonrenewable Energy Resources

Petroleum: Oil and natural gas• Origin of petroleum lies in the alteration by

heat of organic-matter concentrated in source rocks

• Organic matter is transformed into a solid waxy material called kerogen

• At higher temperatures the carbon-carbon bonds break in a process called cracking, eventually producing oil and then gas with progressively increasing temperatures



Petroleum Migration and Traps• Petroleum migrates into reservoir rocks until

it is stopped by an impermeable cap rock• A geologic environment that allows for

economically significant amounts of oil and gas to accumulate underground is termed a petroleum trap

– Common oil and natural gas traps include anticlinal traps, fault traps, and stratigraphic traps


Common oil traps – anticline, fault, salt dome, and stratigraphic



Oil and Natural Gas in Canada• When the cap rock is punctured by drilling, the oil and

natural gas, which are under pressure, migrate from the pore spaces of the reservoir rock to the drill hole

• Western Canada petroleum, especially in Alberta, is found in Devonian reefs and Mesozoic sandstone units

• Important petroleum deposits are being exploited offshore of Newfoundland and Nova Scotia


Petroleum-bearing areas in NA


Nonrenewable Energy ResourcesCoal

• Formed mostly from plant material • Along with oil and natural gas, coal is

commonly called a fossil fuel • The major fuel used in power plants to

generate electricity • Problems with coal use include environmental

damage from mining and air pollution• Most Western Canada coal is Cretaceous-

Tertiary, but coal of Nova Scotia is Pennsylvanian (Upper Carboniferous)


Coal Deposits in Canada



Environmental Effects of Fossil Fuel Use• Urban air pollution

– Air pollutants are airborne particles and gases that occur in concentrations that endanger the health of organisms and disrupt the orderly functioning of the environment



Environmental Effects of Fossil Fuel Use• Two types of pollutants

– Primary pollutants - emitted directly from identifiable sources

– Secondary pollutants – formed when chemical reactions take place among primary pollutants



Environmental Effects of Fossil Fuel Use• Carbon dioxide and global warming

– Burning fossil fuels produces carbon dioxide which is one of the gases responsible for warming the lower atmosphere

– CO2 is not the only gas responsible for global warming




– Greenhouse effect – the atmosphere is transparent to incoming short-wavelength solar radiation. However, the outgoing long-wave radiation emitted by Earth is absorbed in the lower atmosphere, keeping the air near the ground warmer


Heating of the Atmosphere




– It appears that global temperatures have increased (global warming) due to a rising level of atmospheric carbon dioxide

– Canada’s target under Kyoto Protocol is to reduce greenhouse gas emissions to 6% below 1990 levels by 2012


Annual Average Global Temperatures



Unconventional Fossil Fuel Deposits• Heavy Oil Sands

– Mixtures of sediment, water, and bitumen (a viscous black tar-like material)

– Several substantial deposits around the world, including huge reserves in Alberta

– Obtaining oil from tar sands is costly, but will play a major role as global conventional petroleum supplies decrease



Unconventional Fossil Fuel Deposits• Oil shale

– Contains enormous amounts of untapped oil

– Currently, because of world markets and with current technologies, not yet economic to extract


Unconventional Fossil Fuel Resources in North America


Nonrenewable Energy ResourcesUnconventional Fossil Fuel Deposits

• Methane Hydrates – Solid substance with methane surrounded by water molecule

cages

– Found in permafrost and continental shelves

– Currently uneconomic and many environmental concerns

Methane hydrate from 850 metre deep seafloor west of Vancouver

Island, B.C.


Nonrenewable Energy ResourcesUnconventional Fossil Fuel Deposits

• Coal Bed Methane – Heating of coaly organic matter liberates methane

– Currently uneconomic and groundwater contamination concerns

Nuclear Energy – Nuclear fission and CANDU Reactors

– Uranium occurrences

– Obstacles to development


Renewable Fuel Sources

Organic-Based Sources – Landfill Methane

– Biomass Energy

Hydroelectric Power– Generated by falling water

– Canada is a world leader in hydroelectricity production; most energy produced in large dams

– 62% of Canada’s electricity is hydro-generated


Electricity Generation Sources in Canada and a Hydroelectric Dam in Quebec


Renewable Fuel SourcesAlternate energy sources

• Possible alternate energy sources– Solar Energy

– Wind Energy

– Geothermal Energy

– Tidal Power


Solar Panels in Edmonton (left) and a Wind Farm near Pincher Creek, Alberta (right)


End of Chapter 21

copyright (c) 2005 pearson education canada, inc.21-1 powerpoint presentation stan hatfield....

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mineral resources ore

magmatic deposits

energy resources

identified deposits

wind slide

useful metallic minerals