Minerals

The honour of being the first to suggest possible economic mineral deposits in Antarctica goes to Borchgrevink who found quartz reefs near Duke of York Island "justifying the belief that in time to come exploration will receive much support from commerce" (Borchgrevink, 1900). Shackleton attempted to finance his expedition in part by floating mining shares. In 1908 at the top of the Beardmore Glacier on their march south, Wild discovered seams of coal between 4 ins and 7-8 ft thick (Shackleton, 1909). In 1912, Wilson found coal seams at all heights in the sandstone cliffs and lumps of weathered coal with fossil plants on Mt Buckley in the Beardmore Glacier. Debenham also discovered coal on the geological expedition to Granite Harbour. Prior to the Southern Journey, Scott had discovered quartz-containing veins of copper near Cape Bernacchi (Scott, 1913). In Adelie Land, Mawson noted small quantities of ore minerals in gneiss which gave "the possibility of mineral wealth beneath the continental ice-cap" (Mawson, 1915). In 1912, the only mineral prospecting licence ever granted in Antarctica was given by the British Colonial Office to Messrs Chr. Salvesen to explore for minerals in the Antarctic Peninsula (Thomson and Swithinbank, 1985). In 1919, Leo Amery, Under-Secretary of State at the Colonial Office, was arguing for British Annexation of Antarctica, partly on the grounds of the "immense potential value of its fisheries and its mineral resources" (Beck, 1983). Priestley, writing much after the event, also considered that there must be "great and valuable mineral resources" in a continent of that size (Priestley, 1956).

An early major review of the economic potential of Antarctic minerals was presented by Potter (1969). Potter not only listed some of the environmental problems associated with Antarctica but also gave detailed costings of working in Antarctica. It was recognized that the only minerals worth exploiting would be those present in high concentrations and of high value with relatively good access. Minerals rated commercial elsewhere would in most cases be uneconomic because of the high costs involved. Based on consideration of the data then available, Potter considered it unlikely that any mineral (metallic, hydrocarbon or manganese nodules) would be commercially exploitable. Whilst some substantial estimates of Antarctic offshore hydrocarbon resources were made in the 1970s (listed in Zumberge, 1979; Auburn, 1982; and Zorn, 1984) stimulating interest, the conclusions reached by Potter remain essentially unchanged today (cf. Pontecorvo, 1982).

Of the possible mineral resources of Antarctica, it is generally accepted that offshore hydrocarbon resources are the most prospective in the forseeable future but that only giant (about 70 million tonnes of recoverable oil) or supergiant (about 700 million tonnes) fields would be considered commercially worthwhile (Behrendt, 1983b). Nonetheless, exploitation of such deposits would present formidable technical problems. An assessment of the economic potential of these deposits is given by Cook and Davey (this volume) and of the environmental aspects of possible recovery by Gregory (this volume).

The distribution of metallic minerals in Antarctica can be inferred by anology with the distribution of minerals in other segments of the Gondwana Supercontinent (Runnells, 1970). At present, all mineral observations in Antarctica can be classified as mineral occurrences. In spite of much being written, virtually all authors concede that metallic minerals have only limited potential for commercial exploitation in Antarctica (e.g., Wright and Williams, 1974; Holdgate and Tinker, 1979; Lovering and Prescott, 1979; Zumberge, 1979, 1982; Auburn, 1982; Behrendt, 1983b; Gjelsvik, 1983; Quilty, 1984; Shapley, 1985; Budd, 1986a; Roland, 1986; Tessensohn, 1986; Crockett and Clarkson, 1987; Larminie, 1987; Parsons, 1987; Walton, 1988). The reasons for this include the fact that only 2% of Antarctica is ice-free, the harsh climate, the lack of infrastructure, the tremendous transportation problems, the extreme cost of exploration and mining operations and possible environmental problems. An exception to this viewpoint has been presented by de Wit (1985) who argued that platinum mining might be feasible in the Dufek Massif. However, without a full-scale exploration programme, this really is only an assumption based upon geological setting (Larminie, 1987; Parsons, 1987).

Although deep-sea manganese nodules are known to occur in abundance in the Circumpolar siliceous ooze province, the deposits are also considered to have limited economic potential for various reasons (Anderson, this volume).

In drafting the Antarctic Treaty, it was recognized that agreement would have been impossible if mineral resources issues had been considered. This came to be seen as a weakness of the Treaty system and much effort has gone into negotiating a Minerals Regime for the regulation of mineral exploration and exploitation (Auburn, 1982). An agreement was finally reached in Wellington in 1988. Nonetheless, it should be recognized that exploitation of Antarctic mineral resources

(including hydrocarbons) is unlikely in the forseeable future. Quite apart from the considerable technological and environmental problems involved, the high cost of exploiting these deposits means that other sources of minerals or energy can be developed more cheaply elsewhere. This is likely to remain the ultimate barrier to the commercial development of minerals in Antarctica.

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