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Canadian Coal Deposits
Luise Vogler
TU Bergakademie Freiberg, Germany
Abstract. In Canada and around the world you can find coal as a valuable and
abundant fossil fuel resource. The origin goes back to 300 million years ago. It
was a carbon-rich mineral resource which was formed as organic plant matter
decayed and compressed. It was altered by geological processes over millions of
years. It is a black or brownish-black sedimentary rock that is extracted from the
ground by open-pit surface mining or underground mining. Today, coal remains
an enormously important fuel because it generates the largest single source of
electricity worldwide. It also helps produce over 70 % of the world`s steel and is
used by other industrial processes like cement manufacturing.
Introduction
Today Canada is richly loaded with coal. Its coal resources are very distributed
and have diverse attributes. The diversity in the nation`s coal resources puts
Canada in a strong position to respond positively to coal developement
opportunities as national and international coal requirements change.
Coal-bearing strata are found in many areas of Canada, from coastal British
Columbia in the west, to the Atlantic Provinces in the east, and in Northern
Canada (Figure 1). These strata range in age from Devonian to Tertiary, and the
coals range in rank from lignitic to anthracitic.
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Fig.1. Distribution of coal in Canada (modified after Smith, 1989).
The nature of coal occurrences and characteristics vary from region to region.
These differences result from the varying types of vegetation from which the coal
originated; the depths of storage, and the temperatures and pressures at those
depths; as well as the length of time the coal has been forming in the deposit. The
varying amount of mineral matter in a coal deposit may also have a significant
effect on its properties and classification.
The major coal resources in eastern Canada are of Late Carboniferous age, like
those of western Europe and in the Appalachian region of the United States. The
largest coal-bearing region is located in western Canada, stretching from south
Saskatchewan across Alberta into British Columbia. The major coal deposits are
younger, ranging in age from Late Jurrasic to Tertiary. These are characteristically
different from those in the east (Smith, 1989).
Coal deposits originated as peat-forming materials that accumulated at or near
their place of growth, within swamps and marshes occurring in deltaic, alluvial
and lacustrine environments. Major coal-bearing sedimentary basins of Canada are
shown in Figure 2.
Canadian Coal Deposits 3
Fig.2. Major coal-bearing sedimentary basins in Canada (modified after Smith,
1989).
Most Canadian coals are consumed either by carbonization to produce
metallurgical coke, or by combustion to raise steam for electric power generation
(Smith, 1989). Coals that are suitable for the production of metallurgical coke are
referred to as metallurgical coals. Coals that are used to fuel electric power
generating plants are referred to as thermal coals.
Most of Canada`s metallurgical coal deposits are located in the Rocky
Mountain Ranges of southeastern British Columbia and southwestern Alberta, and
in the Inner Foothills Belt of northeastern British Columbia and westcentral
Alberta. And most of Canada`s thermal coal deposits are located in the Interior
Plains of Alberta and Saskatchewan, and in the Outer Foothills Belt of Alberta.
Other major thermal coal resources occur in the coastal and intermontane regions
of British Columbia, and in Northern Canada.
The ranks of coals, from those with the least carbon to those with the most carbon,
are lignite, sub-bituminous, bituminous and anthracite. In addition to carbon, coals
contain hydrogen, oxygen, nitrogen and varying amounts of sulphur. High-rank
coals are high in carbon and therefore they bare great heat value, but low in
hydrogen and oxygen. Low-rank coals are low in carbon but high in hydrogen and
oxygen content.
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The highest rank, and hardest coal, is anthracite. It does not meet the major
current conventional thermal and metallurgical market requirements. It is found
almost exclusively in the northern intermontane region of British Columbia, and in
the Yukon Territory. Smaller resources occur in the Rocky Mountain Front
Ranges and Inner Foothills of Alberta.
Bituminous coal, ranked second highest, is found in
Alberta, British Columbia and the Maritimes. On one
side bituminous coal can be metallurgical, used to make
coke for the steel industry, or thermal, used to generate
electricity. In 2002, bituminous coal accounted for 29.7
million tonnes (Mt) or approximately 45 % of Canada's
total coal production (Coal Association of Canada,
2006).
Sub-bituminous coal is softer than bituminous and
contains more moisture, making it less economic to
transport long distances. Alberta is the only province
where sub-bituminous coal is mined. In 2001, 25.4 Mt
were produced to generate over 70 % of the province's
electricity (Coal Association of Canada, 2006).
Fig.3. Ranks of coal Lignite is a soft, brown or black coal found in southern
(modified after Coal Saskatchewan, southeastern Alberta and southwestern
Association of Manitoba. Only the Saskatchewan deposits are
Canada, 2006). currently being mined and production is used to
generate approximately 70 % the province's electricity.
In 2001, 11.4 Mt of lignite coal were produced in Saskatchewan (Coal Association
of Canada, 2006).
Many Canadian coals show good liquefaction and gasification potential, and
some may be ideally suited for in situ gasification.
Coal Regions of Canada
Coastal British Columbia
Vancouver Island, Queen Charlotte Islands and the coastal mainland of
southwestern British Columbia contain coals that vary in rank from lignitic to
anthracitic occurrence in Late Mesozoic and Tertiary strata. Along the east coast
of Vancouver Island the most promising resource potential is within the Upper
Cretaceous Nanaimo Group which contains high volatile bituminous coals. Their
attributes are almost identical to those of other coals used to fuel conventional
thermal electric generating plants in Canada and in other parts of the world.
On Graham Island in the Queen Charlotte Islands and in the Fraser Basin on the
coastal mainland occur low rank Tertiary coals. Although large quantities may
exist in both areas, they are much too deep for economical surface mining.
Significant lignite resources occur in the lower nonmarine member of the
Tertiary Skonun Formation. The Skonun Coalfield consists of thirteen beds of
Canadian Coal Deposits 5
woody lignite and it has a thickness of 6 m occur within 60 m of shale. The
thickest reported bed is 1.8 m. These beds occur in a faulted, west-plunging,
moderatly appressed anticline.
Coal deposits of Graham Island vary from the rank low volatile bituminous to
anthracite, from high to medium volatile bituminous and from lignite to sub-
bituminous.
Minor Eocene lignite and carbonaceous sandstone deposits in the Lang Bay
area of the coastal mainland are not commercially significant in the context of
conventional coal exploitation. However, some contain high concentration of
germanium and gallium. The commercial recovery of these rare metals, which are
primarily contained in the vitrinite fraction of the lignite, is presently being
investigated.
Coal deposits occur in Lower Cretaceous strata at the north end of Vancouver
Island. These deposits are essentially unexplored and are not well understood.
Jurassic to Cretaceous strata on Graham Island contain coal deposits that have
been explored.
Intermontane British Columbia
Intermontane British Columbia has been divided into a northern and a southern
region.
In the northern region, coal deposits occur in strata ranging from Lower
Jurassic to Lower Tertiary. The most commercially significant of these deposits
are within Upper Jurassic and Lower Cretaceous strata. These coals vary in rank
from high volatile bituminous to anthracitic. No high quality coking coals have
been identified. The rank of coals in the northern intermontane region ranges from
lignitic to anthracitic.
In the southern region, all major coal deposits are Tertiary in age and have
ranks ranging between lignitic and high volatile bituminous. Evolution and
developement of the coal-bearing sedimentary basins in the region were largely
tectonically controlled. Some of the coal occurrences were deposited within fault-
controlled graben-like structures and others exist as erosional remnants of larger
sedimentary basins. The major coal measures of the region are of middle Eocene
age, only the Quensel and Bowron River coalfields are of late Eocene or younger.
The quality of the coals varies significantly among the deposits and within each
deposit. The rank of coal ranges from lignitic to bituminous.
Canadian Rocky Mountains
The Canadian Rocky Mountains are devided into the Rocky Mountain Main
Ranges, the Rocky Mountain Front Ranges, the Foothills and the Interior Plains.
The Rocky Mountain Main Ranges contain mostly Precambrian, Cambrian,
some Devonian and Mississippian rock units.
The Rocky Mountain Front Ranges and Foothills of British Columbia and
Alberta contain more than 95 per cent of Canada`s bituminous coal resources. The
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region is devided into three distinct coal-bearing regions – Rocky Mountain Front
Ranges, Inner Foothills Belt and Outer Foothills Belt.
The Rocky Mountain Front Ranges are characterized by thrust sheets of mainly
Upper Paleozoic carbonates bounded by faults that extend for tens of kilometres in
length and have displacements up to several kilometres. In the Rocky Mountain
Front Ranges occur Jurassic to Cretaceous coal measures.
Most of Canada's lignitic and sub-bituminous coal desposits occur within the
Interior Plains of the Rocky Mountains. The coal commonly occurs close to the
surface, and in near-horizontal beds. These are conditions that are often ideal for
large-scale strip mining operations. Most of the production is used to fuel mine-
mouth electric power generating stations.
Near surface stratigraphic sequences in the Interior Plains were stored mainly in
Late Cretaceous and Tertiary times.
Generally, coal measures of the Interior Plains have not been tectonically
deformed except in a regional sense. However, they have been deformed to
varying degrees by differential compaction. Additionally, strata occurring near the
bedrock surface have been variably folded and faulted by overriding glacial
movements. This deformation tends to complicate mining operations.
Most of Canada`s metallurgical coal deposits are located in the Rocky
Mountain Ranges of southeastern British Columbia and southwestern Alberta, and
in the Inner Foothills Belt of northeastern British Columbia and westcentral
Alberta.
Fig.4. Canadian Rocky Mountains – A Cross Section Through the Rocky
Mountains to the Interior Plains (modified after Mussieux and Nelson, 2000).
Atlantic Provinces: New Brunswick, Nova Scotia and Newfoundland
In the Atlantic Provinces of New Brunswick, Nova Scotia and Newfoundland in
eastern Canada occur significant coal deposits. These deposits are contained in
strata stored of Carboniferous.
The Pictou Coalfield contains the only known low volatile bituminous coal in
eastern Canada.
Canadian Coal Deposits 7
The Sydney Coalfield contains most of the coal deposits and reserves of the
Atlantic Provinces. More than 98 per cent of the coalfield is located offshore.
Only a very small part of the field is on land with the greater part of it beneath the
Atlantic Ocean. The rank of coals varies enormously, increasing to the east and
with depth.
There are four small coalfields along the west coast of Cape Breton Island.
They are Port Hood, Mabou, Inverness and St. Rose Chimney Corner. The quality
of the coal, structural conditions and the extensive submarine position of these
small fields have restricted their exploration and developement.
The Atlantic-Province coals are typically high in sulphur content relative to
western Canadian Cretaceous coals. They are generally fuels for conventional
coal-fired electric power generating stations, and often have characteristics
suitable for metallurgical coke-making.
Most coal resources of the Atlantic Provinces range in rank between high
volatile C bituminous and high volatile A bituminous. Many of these coals are
suitable as both thermal and metallurgical coals.
Northern Canada
Coal resource quantities of Northern Canada are very large, most deposits have
generally not been well explored because of their distance and other factors that
have reduced against possible exploitation. The coal resources that occur in the
Yukon Territory and District of Mackenzie will be considered separately from
those in the Arctic Archipelago. All coal resources of immediate interest occur in
the Yukon Territory and District of Mackenzie. Coal beds in northern Canada
occur in strata from Devonian to Tertiary. All rank classes from lignitic to
anthracitic exist in the region.
In the Yukon Territory and the western District of Mackenzie the in situ coals
contain less than 30 % and occasionally less than 15 % ash. Sulphur is less than
0.5 % with the exception of the Mississippian coals in the Nahanni region, which
have sulphur by 2 %. Most coals appear to be suitable fuels for conventional coal-
fired electric power generating plants, and some are suitable for metallurgical
coke-making.
In the Middle and Upper Devonian clastic wedge, that extends from Ellesmere
Island to Banks Island in the Arctic Archipelago, occur the oldest significant coal
beds in Canada. The Arctic Archipelago contains both lignite and higher rank
coals.
Canada`s Coal Production through the Years
Since the 1970s, Canada has been a large producer of coal. In 1996, the coal
production was a record about 75.95 Mt (Figure 3). But Canada is not one of the
world`s major producers, because most Canadian coal resources are located in
western Canada, Alberta and eastern British Columbia. The transportation to
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foreign markets requires long rail haulage (600 km or more) to ocean ports, thus
increasing shipping costs and thereby limiting export involved (Cranstone, 2003).
Although Canada produces coal in the east provinces. The transportation costs
are not only high, but in the east the St. Lawrence Seaway and some of the Great
Lakes are even closed to navigation for two or three months each year as result of
winter ice conditions.
On the other side, the relatively low sulphur content of coal from western
Canada (about 0.5 % sulphur) makes it much more environmentally acceptable
than is the high-sulphur coal from Pennsylvania (about 3 % sulphur) (Cranstone,
2003).
Fig. 5. Canadian Coal Production, 1867-2000 (modified after Cranstone, 2003).
Mining and Using of Coal
According to Coal Accociation of Canada 2006, in 2002, Canada produced 66.6
million tonnes (Mt) of coal. About 40 % of that, 26.8 Mt, was exported to over 20
different countries in the Pacific Rim, Europe and South America. Japan, Canada's
largest coal customer, purchased 10.7 Mt of coal in 2001. Over 97 % (10.4 Mt) of
that coal exported to Japan was metallurgical coal, used for making steel.
Canadian Coal Deposits 9
Of the ten provinces, Ontario and Alberta consume by far the greatest amounts
of coal. In 2001, Alberta used 25.5 Mt, about 42 % of the coal consumed in
Canada. In the same year, Ontario used 19.1 Mt, or about 32 % of Canada's coal
use. Four other provinces use coal to generate electricity: Saskatchewan,
Manitoba, Nova Scotia and New Brunswick.
Although much of its production is used domestically, Canada imported 22.1
Mt of coal for industrial use in Ontario and Québec and for electrical generation in
Ontario and New Brunswick (Coal Association of Canada, 2006).
Future interests
In most sedimentary basins in Canada coal beds occur in a variety of forms and
amounts. Coal bed thickness, geographical location, depth from surface and coal
quality are primary indicators of a deposit's potential utility.
According to Geological Survey of Canada 2006, deposits of future interest
consider coal beds that are less than 60 cm thick (with the exception of resources
in New Brunswick, where thinner beds are currently mined), occurring at depths
that are greater than 600 m from surface, (with the exception of resources in Nova
Scotia, where mining to much greater depths is currently planned).
Coal is second only to oil as an energy source in the world. Approximately 70
% of the world's coal production is used to generate 40 % of the world's
electricity, 12 % is made into coke used to produce 70 % of the world's steel, and
the remaining 18 % is used for other industrial and domestic purposes. 18 % of
Canada's electricity is generated by using coal.
In Canada, all cement plants, with the exception of a white cement plant in
Ontario, use coal in their manufacturing process. A total of 1.2 million tonnes of
coal was used to produce 13.5 million tonnes of cement in 2003.
In 2005, Canada produced 67.3 Mt of coal, a small increase over 2004’s
production of 66.5 Mt. The increase was mainly from Alberta, which produced
28.6 Mt of coal in 2005. Production from British Columbia and Saskatchewan
remained at a level similar to 2004 (Coal Association of Canada, 2006).
Canada exported 28.2 Mt of coal - 26.7 Mt was coking coal and 1.5 Mt was
thermal coal. In 2005, compared with 2004, Canada’s export volume increased by
8 %. Asia is the largest market for Canada - the exports increased 24 % and its
volume reached 15 Mt in 2005, compared with 12 Mt in 2004 (Coal Association
of Canada, 2006).
With rapid improvement in emissions reduction technology, better
environmental management in mining operations, widespread availability
worldwide, and substantial remaining reserves, coal will continue to play a vital
role in providing the world's energy well into the foreseeable future.
10 Luise Vogler
References
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Paper 89-4, pp. 18-105
Patching, T.H. (1985) Coal in Canada, The Canadian Institute of Mining and
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Muise, D.A..; McIntosh, R.G. (1996) Coal Mining in Canada: A Historical and
Comparative Overview, National Museum of Science and Technology, pp. 52-55
Cranstone, D. (2003) Canada: A History of Mining and Mineral Exploration and
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