Coal

Coal is a combustible rock of organic origin composed mainly of carbon along with variable quantities of other elements, chiefly hydrogen, sulfer, oxygen and nitrogen. It is a sedimentary rock formed from accumulated vegetable matter that has been altered by decay and by various degrees of temperature and pressure over millions of years. Interlayered with other sedimentary rocks, it forms beds ranging from less than a millimetre to many metres thick. The considerable diversity of coal type, grade and rank depends on the differences in mode of formation.

Black coal is so called because of its colour. It varies from having a bright, shiny lustre to being very dull, and from being relatively hard to soft. The term 'black coal' is used in Australia to refer to anthracite, as well as bituminous and sub-bituminous coals (Table 3.7). Black coal is higher in energy and has lower moisture content than brown coal. Brown coal, also called lignite, is a low-ranked coal with high moisture content that is used mainly to generate electricity.

Table 3.7 Coal classification terminology in Australia and Europe.
Coal rank Australian terminology European terminology
Source: Geoscience Australia.
Anthracite Black coal Black coal
Bituminous coal Black coal Black coal
Sub-bituminous coal Black coal Brown coal
Lignite Brown coal Brown coal

Throughout history, coal has been a useful resource for heat, electricity generation and for industrial processes such as metal refining. Coal is Australia's largest energy resource and around 60% of the nation's electricity is currently produced in coal-fired power stations. Black coal is also used to produce coke (metallurgical or coking coals), which is mainly used in blast furnaces that produce iron and steel. Black coal is used also in other metallurgical applications, cement manufacturing, alumina refineries, paper manufacture and a range of industrial applications.

Black coal resources occur in New South Wales, Queensland, South Australia, Tasmania and Western Australia (Figure 3.4) but New South Wales (23%) and Queensland (63%) have the largest share of Australia's total identified in situ resources (Figure 3.5). These two states are also the largest coal producers. While Australia's mineable black coals range from Permian to Jurassic in age (280 to 150 million years old), most of Australia's black coal resources are of Permian age. Australia's principal black coal producing basins are the Bowen (Queensland) and Sydney (New South Wales) Basins. Locally important black coal mining operations include Collie in Western Australia, Leigh Creek in South Australia and Fingal and Kimbolton in Tasmania.

Brown coal occurs in South Australia, Western Australia, Tasmania, Queensland and Victoria (Figure 3.4), predominantly in Tertiary basins (50 to 15 million years old). The Gippsland Basin in Victoria contains a substantial world-class deposit where seams can be up to 330 m thick. The Otway Basin (Victoria), the Murray Basin (Victoria and South Australia), the North St Vincents Basin (South Australia) and the Eucla Basin (Western Australia) also contain significant brown coal resources. Minor resources occur in Tasmania's Longford Basin. Currently, brown coal is only mined in Victoria where the open-cut mines at Anglesea, Loy Yang, Yallourn and Hazelwood supply coal to nearby power stations. Brown coal is also mined at Maddingley to produce soil conditioners and fertilisers. Other products from Victorian brown coal are briquettes for industrial and domestic use and low-ash and low-sulphide char products.

In Australia, nearly 80% of coal is produced from open-cut mines in contrast with the rest of the world where open-cut mining only accounts for 40% of coal production. Open-cut mining is cheaper than underground mining and enables up to 90% recovery of the in situ resource. Coal may be used without any processing other than crushing and screening to reduce the fragments to a useable and consistent size. However, black coal is often washed to remove pieces of rock or mineral that may be present. This also reduces ash and improves overall quality.

Figure 3.4 is a map of Australia showing the names, locations and sizes of major coal provinces overlain with the locations of both black and brown coal deposits and operating mines. The map also shows the state boundaries and capital cities. Brown coal basins are coloured brown and located in Victoria, South Australia and the southeast of Western Australia. A small brown coal basin also occurs in Tasmania. All of these states host brown coal mineral deposits but only Victoria has operating mines. Black coal basins are coloured grey and are located near Perth and the Kimberley region of Western Australia, the northern part of South Australia, large portions of eastern and central Queensland, the northeast of New South Wales and the eastern part of Tasmania. Black coal mineral deposits and operating mines occur in all these states with the greatest concentrations of deposits and mines occurring in the Newcastle-Hunter region of New South Wales and the hinterland of the Gladstone-Rockhampton region of Queensland.

Figure 3.4 Australia's operating black and brown coal mines as at December 2012.
Source: Geoscience Australia.

Resources and Reserves

Table 3.8 Australia's resources of black coal and world figures as at December 2012.
  Units JORC Reserves (% of EDR) Economic Demonstrated Resources (EDR) Paramarginal Demonstrated Resources Submarginal Demonstrated Resources Inferred Resources Accessible EDR Mine Production in 2012 World Economic Resources World Mine Production in 2012
Source: Geoscience Australia, the Bureau of Resources and Energy Economics, the World Energy Council and the World Coal Association; Paramarginal and submarginal demonstrated resources are subeconomic at this time; Mt = million tonnes; n.a. = not applicable; (a) raw coal; (b) saleable coal.
In situ Mt n.a. 77 589 1613 5341 89 194 n.a. n.a. n.a. n.a.
Recoverable Mt 20 662 (38%) 61 082 1134 3984 64 184 54 200 501 (a) 665 000 6637 (b)

Figure 3.5 comprises two pie charts side by side. The one on the left shows the percentage of Economic Demonstrated Resources (EDR) of black coal held by each state and territory in Australia as at December 2012. The chart on the right shows the percentage of total black coal resources held by each state and territory in Australia as at December 2012. Queensland has the most black coal EDR with 60% followed by New South Wales with 36%. Similarly, Queensland has the greatest total black coal resources with63% followed by New South Wales with 23% and South Australia with 11%. Western Australia and Tasmania also have a small proportion of black coal resources.

Figure 3.5 Percentages of Economic Demonstrated Resources and total resources of black coal held by the states and territories in Australia. Total resources comprise all Demonstrated and Inferred Resources. Numbers are rounded so might not add up to 100% exactly.
Source: Geoscience Australia.

Table 3.9 Australia's resources of brown coal and world figures as at December 2012.
  Units JORC Reserves (% of EDR) Economic Demonstrated Resources (EDR) Paramarginal Demonstrated Resources Submarginal Demonstrated Resources Inferred Resources Accessible EDR Mine Production in 2012 World Economic Resources World Mine Production in 2012
Source: Geoscience Australia, the Bureau of Resources and Energy Economics, the World Energy Council and the World Coal Association; Paramarginal and submarginal demonstrated resources are subeconomic at this time; Mt = million tonnes; n.a. = not applicable; (a) There are no JORC compliant reserve estimates available for brown coal.
In Situ Mt n.a. 49 035 37 465 16 873 123 240 n.a. n.a. n.a. n.a.
Recoverable Mt (a) 44 164 33 402 15 185 102 502 34 095 66.73 195 000 1041

Figure 3.6 comprises two pie charts side by side. The one on the left shows the percentage of Economic Demonstrated Resources (EDR) of brown coal held by each state and territory in Australia as at December 2012. The chart on the right shows the percentage of total brown coal resources held by each state and territory in Australia as at December 2012. In both charts, Victoria totally dominates with 99% of the brown coal EDR and 97% of the total resources. Western Australia holds the remaining 1% of EDR with South Australia and Tasmania also having a tiny share of the total resources.

Figure 3.6 Percentages of Economic Demonstrated Resources and total resources of brown coal held by the states and territories in Australia. Total resources comprise all Demonstrated and Inferred Resources. Numbers are rounded so might not add up to 100% exactly.
Source: Geoscience Australia.

World Ranking

Table 3.10 World economic resources for coal.
Rank Country Black Coal (Mt) Brown Coal (Mt) Total Coal (Mt) Percentage (%)
Source: BP plc and Geoscience Australia; Mt = million tonnes; Percentages are rounded so might not add up to 100% exactly.
1 United States of America 108 501 128 794 237 295 28%
2 Russia 49 088 107 922 157 010 18%
3 China 62 200 52 300 114 500 13%
4 Australia 37 100 39 300 76 400 9%
5 India 56 100 4500 60 600 7%
6 Germany 99 40 600 40 699 5%
7 Ukraine 15 351 18 522 33 873 4%
8 Kazakhstan 21 500 12 100 33 600 4%
9 South Africa 30 156 0 30 156 4%
10 Columbia 6366 3800 10 166 1%
  Others     69 121 8%
  Total     860 000  
Table 3.11 World production for coal.
Rank Country Black Coal (Mt) Brown Coal (Mt) Total Coal (Mt) Percentage (%)
Source: International Energy Agency and the Bureau of Resources and Energy Economics; Mt = million tonnes; Percentages are rounded so might not add up to 100% exactly.
1 China 2344 1127 3471 46%
2 United States of America 917 73 991 13%
3 India 539 41 580 8%
4 Australia 345 70 414 5%
5 Russia 256 78 334 4%
6 Indonesia 197 179 376 5%
7 South Africa 253 0 253 3%
8 Germany 12 177 189 2%
9 Poland 76 63 138 2%
10 Kazakhstan 111 6 117 2%
  Others     737 10%
  Total     7600  

Trends

A major reassessment of New South Wales coal resources during 1986 by the New South Wales Department of Mineral Resources and the Joint Coal Board resulted in a large increase in black coal EDR as reported in 1987 ('a' in Figure 3.7).

EDR for black coal has declined since 1998 because of the combined impact of increased rates of mine production and mining companies re-estimating ore reserves and mineral resources more conservatively to comply with requirements of the JORC Code. In 2009, black coal EDR increased significantly, mainly because of the discovery and delineation of additional resources as a result of high levels of exploration and through reclassification of resources.

EDR for brown coal rapidly increased during the mid-1970s as the brown coal resources in the Gippsland Basin of Victoria were more formally delineated (Figure 3.8). EDR has remained at similar levels since that time.

Figure 3.7 shows the Economic Demonstrated Resources (EDR) of black coal (recoverable) from 1975 to 2012. There is one line on the graph. The vertical axis is labelled in thousands of millions of tonnes beginning at 0 and in increments of 10 000 million. The horizontal axis is labelled with the year starting with 1975 and ending with 2012. In the graph, the line begins at 19 500 million tonnes in1975 and climbs steadily to about 34 000 million tonnes in 1986. From 1987 there was a sharp increase in coal resources to a peak of 52 000 million tonnes in 1992 and 1993. EDR for coal declined from 1998 to a low of about 38 300 million tonnes in 2003 but has since climbed to around 61 000 million tonnes in 2012.

Figure 3.7 Trends in Economic Demonstrated Resources for black coal (recoverable) since 1975.
Source: Geoscience Australia.

Figure 3.8 shows the Economic Demonstrated Resources (EDR) of brown coal (recoverable) from 1975 to 2012. There is one line on the graph. The vertical axis is labelled in thousands of millions of tonnes beginning at 0 and in increments of 10 000 million. The horizontal axis is labelled with the year starting with 1975 and ending with 2012. In the graph, the line begins at 12 600 million tonnes in1975 and climbs sharply to 38 900 million tonnes in 1977. From this point the line is mostly flat, ranging from a lows of 36 1000 million tonnes to highs of 44 220 million tonnes.

Figure 3.8 Trends in Economic Demonstrated Resources for brown coal (recoverable) since 1975.
Source: Geoscience Australia.

Resource to Production Ratio

Table 3.12 Indicative years of black and brown coal resources (rounded to the nearest 5 years) as a ratio of Accessible Economic Demonstrated Resources divided by the production rate for each year.
Year 1998 2003 2008 2009 2010 2011 2012
Source: Geoscience Australia.
AEDR/Production Black Coal 180 110 90 100 90 110 110
AEDR/Production Brown Coal 630 440 490 470 495 510 510