Catalogue of world wide diamond and kimberlite occurrences: a selective and annotative approach

Kimberlites occur on every continent and the total number of known primary host rock occurrences is generally accepted as 5000, of which 500 are diamondiferous, 50 have been or are being mined and 15 are large active mines. Clifford's Rule is shown to be valid in that economic kimberlites occur...

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Veröffentlicht in:Journal of geochemical exploration 1995-03, Vol.53 (1), p.73-111
Hauptverfasser: Janse, A.J.A. (Bram), Sheahan, Patricia A.
Format: Artikel
Sprache:eng
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Zusammenfassung:Kimberlites occur on every continent and the total number of known primary host rock occurrences is generally accepted as 5000, of which 500 are diamondiferous, 50 have been or are being mined and 15 are large active mines. Clifford's Rule is shown to be valid in that economic kimberlites occur only on Archons, i.e. cratonic regions underlain by Archaean basement, whereas economic lamproites occur on some Protons, i.e. Proterozoic mobile belts adjacent to Archons. These Archons are distributed world wide in twelve potentially diamond producing regions which occur on seven continents. Three of these twelve regions, i.e. North America, Europe and Antarctica do not have any diamond mines, although significant primary diamond deposits have been found on the first two which will probably be mined in the next decade. The South American continent contains several cratons including the Guyana, Guaporéand Sa˜o Francisco Cratons which each enclose Archons. These are predominantly located in remote, tropical, heavily forested areas which have not yet been fully explored. Most kimberlites discovered so far in South America lie in Protons, i.e. Proterozoic mobile belts encircling the Archons and are not economic. Therefore almost all production from South America is from alluvial deposits. There is no commercial diamond production from the North American continent, although there are many occurrences of diamonds, kimberlites and lamproites. A great staking rush has taken place in Canada in the Northwest Territories, Alberta, Saskatchewan, Ontario and Québec and is still continuing. Two, and possibly five, diamond mines may be developed in the next decade. Diamond prospecting is proceeding at a fast pace in Canada and in a more limited way in the United States. The African continent contains three large cratons, the South African, Central African and West African cratons. The South African Craton includes the large Kalahari Archon on which the majority of the world's active major kimberlite diamond mines are located in South Africa, Botswana, Zimbabwe and Swaziland. They comprise 11 kimberlite pipe mines and 3 kimberlite dyke mines. Large alluvial, beach and off-shore deposits also produce a large proportion of the world's total. The Central African Craton includes the Lunda-Kasai and the Tanzanian Archons which each contain one active kimberlite pipe mine in Zaire and in Tanzania. Several large kimberlite pipes in Angola may become mines in the next decade. The craton
ISSN:0375-6742
1879-1689
DOI:10.1016/0375-6742(94)00017-6