| Title | Kimberlite diamond deposits |
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| Author | Kjarsgaard, B A |
| Source | Mineral deposits of Canada: a synthesis of major deposit-types, district metallogeny, the evolution of geological provinces, and exploration methods; by Goodfellow, W D (ed.); Geological Association of
Canada, Mineral Deposits Division, Special Publication no. 5, 2007 p. 245-272 |
| Image |  |
| Year | 2007 |
| Alt Series | Earth Sciences Sector, Contribution Series 20070197 |
| Publisher | Geological Association of Canada, Mineral Deposits Division (St. John's, NL, Canada) |
| Document | serial |
| Lang. | English |
| Media | paper; DVD; digital |
| Related | This publication is contained in Mineral deposits of Canada:
a synthesis of major deposit-types, district metallogeny, the evolution of geological provinces, and exploration methods |
| File format | pdf |
| Province | British Columbia; Alberta; Saskatchewan; Manitoba; Ontario; Quebec; New Brunswick; Nova Scotia; Prince Edward Island; Newfoundland and Labrador; Northwest Territories; Yukon; Nunavut; Canada |
| NTS | 1; 2; 3; 10; 11; 12; 13; 14; 15; 16; 20; 21; 22; 23; 24; 25; 26; 27; 28; 29; 30; 31; 32; 33; 34; 35; 36; 37; 38; 39; 40; 41; 42; 43; 44; 45; 46; 47; 48; 49; 52; 53; 54; 55; 56; 57; 58; 59; 62; 63; 64; 65;
66; 67; 68; 69; 72; 73; 74; 75; 76; 77; 78; 79; 82; 83; 84; 85; 86; 87; 88; 89; 92; 93; 94; 95; 96; 97; 98; 99; 102; 103; 104; 105; 106; 107; 114O; 114P; 115; 116; 117; 120; 340; 560 |
| Lat/Long WENS | -141.0000 -50.0000 90.0000 41.7500 |
| Subjects | economic geology; mineralogy; mineral occurrences; mineral deposits; mineralization; diamond; kimberlites; lamprophyres; lithosphere; pressure-temperature conditions; mantle; geothermal gradient;
xenoliths; igneous rocks; intrusive rocks; volcanic rocks; alteration; mineral exploration; mineral potential; Precambrian; Proterozoic; Paleozoic; Mesozoic |
| Illustrations | sketch maps; graphs; histograms; plots |
| Program | Consolidating Canada's Geoscience Knowledge |
| Program | Targeted Geoscience Initiative (TGI-3), 2005-2010 |
| Released | 2007 01 01 |
| Abstract | Diamonds have formed over a signifi cant period of the Earth's history, from ca. 3.57 Ga to 88 Ma, and probably to present day. Macrodiamonds are interpreted to crystallize from low-density fl uids, or
carbon- and water-rich melts at pressures >~4.0 GPa and temperatures <~1350°C. These P-T conditions are met within thick, old lithospheric mantle roots that have low paleogeothermal gradients, and these roots lie under ancient continental nuclei.
Kimberlite-hosted diamond mines occur in these cratonic shield regions that are older than 2.5 Ga. Macrodiamonds are transported as xenocrysts from the mantle to the surface by kimberlite magmas. The initiation of kimberlite magmatism is at depth in
the asthenospheric mantle (>150 km), although the initiation and generation of kimberlite magma is poorly understood. Kimberlites magmas generate a range of rocks that form a wide variety of landforms and intrusions, in many aspects similar to that
generated by small-volume alkali basaltic volcanic systems. Kimberlite bodies typically form from multiple intrusive and/or extrusive events; these discrete events form distinct kimberlite phases. These individual kimberlite phases are characterized
by differing textures, mineralogy and geochemistry, and diamond grade, size populations and morphology, and value. |
| GEOSCAN ID | 224183 |
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