| Title | Diamonds in Alberta: studies of potential host rocks of deep-seated origin and applications of indicator mineral exploration techniques |
| Download | Download (whole publication) |
| |
| Licence | Please note the adoption of the Open Government Licence - Canada
supersedes any previous licences. |
| Author | Kjarsgaard, B A |
| Source | Exploring for minerals in Alberta: Geological Survey of Canada geoscience contributions, Canada-Alberta Agreement on Mineral Development (1992-1995); by Macqueen, R W (ed.); Geological Survey of Canada,
Bulletin 500, 1997 p. 185-207, https://doi.org/10.4095/209213  Open Access |
| Year | 1997 |
| Publisher | Natural Resources Canada |
| Document | serial |
| Lang. | English |
| Media | paper; on-line; digital |
| Related | This publication is contained in Exploring for minerals in
Alberta: Geological Survey of Canada geoscience contributions, Canada-Alberta Agreement on Mineral Development (1992-1995) |
| File format | pdf |
| Province | Alberta |
| NTS | 72E; 72L; 72M; 73D; 73E; 73L; 73M; 74D; 74E; 74L; 74M; 82G/01; 82G/08; 82G/09; 82G/10; 82G/15; 82G/16; 82H; 82I; 82J/01; 82J/02; 82J/07; 82J/08; 82J/09; 82J/10; 82J/11; 82J/13; 82J/14; 82J/15; 82J/16;
82N/08; 82N/09; 82N/15; 82N/16; 82O; 82P; 83A; 83B; 83C; 83D/09; 83D/15; 83D/16; 83E/01; 83E/02; 83E/05; 83E/06; 83E/07; 83E/08; 83E/09; 83E/10; 83E/11; 83E/12; 83E/13; 83E/14; 83E/15; 83E/16; 83F; 83G; 83H; 83I; 83J; 83K; 83L; 83M; 83N; 83O; 83P;
84 |
| Lat/Long WENS | -120.0000 -110.0000 60.0000 49.0000 |
| Subjects | industrial minerals; geochemistry; surficial geology/geomorphology; igneous and metamorphic petrology; kimberlites; diamond; pipes; plutonic rocks; dykes; minettes; igneous rocks; rubidium strontium
dates; radiometric dates; lithology; petrographic analyses; mineral assemblages; analyses; major element analyses; whole rock analyses; trace element analyses; geochemical analyses; mineralogical analyses; exploration methods; ice movement
directions; glacial deposits; paleocurrent directions; paleogeography; provenance; Precambrian |
| Illustrations | sketch maps; analyses |
| Program | Canada-Alberta Agreement on Mineral Development, 1992-1995 |
| Released | 1997 10 01 |
| Abstract | The recent identification of subsurface crystalline basement domains of Archean and Paleoproterozoic age in Alberta is geologically favourable for the occurrence of kimberlite- or lamproite-hosted
diamond deposits. Throughout Alberta, diamonds and indicator minerals have been recovered from various Quaternary glacial deposits and modern drainage systems, largely as a result of intensive diamond exploration prospecting since 1990. Recently,
pipes containing crater-facies rocks have been discovered in the Grande Prairie area. These pipes, together with strongly potassic igneous rocks exposed in the Milk River area, constitute the only currently known occurrences in Alberta of magmatic
rocks of deep-seated origin that have the potential to be diamond-bearing. The "Sweet Grass Intrusives" outcrop as hypabyssal intrusive rocks (dykes, plugs) as well as extrusive rocks in the Milk River area. Combined whole-rock major- and trace-
element chemistry, and isotopic studies, coupled with petrographic studies and mineral chemistry, demonstrate that these rocks are minettes, which were derived from a veined, lithospheric mantle source region at >100 km depth (i.e., P >30 kb; garnet
lherzolite assemblage). Major- and trace-element chemistry of Cr-spinels from the Sweet Grass minettes indicate that existing classification and discrimination diagrams do not separate minette Cr-spinels from kimberlite or lamproite Cr-sprinels. This
is important, as Cr-spinel is used commonly in surficial diamond indicator mineral exploration programs in Alberta. Both the Hinton (central Alberta) and Legend (southern Alberta) areas, suggested to have high diamond potential, have complex
sedimentological histories (multiply recycled indicator minerals), and the primary source(s) of the diamonds and indicator minerals are still unknown. |
| GEOSCAN ID | 209213 |
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