The northern Churchill Province is an intensely explored, yet poorly researched target area for diamonds. I examined the mantle sources and residence history of diamonds from Aviat, located on the Melville Peninsula. Aviat diamonds display a δ13C range extending far below the average mantle value of -5‰ indicating eclogitic sources must be present. Crustal protoliths, carrying the organic matter implied by strongly 13C depleted diamond compositions, likely were supplied via subduction. The main population of diamonds around -5‰ may be either eclogitic or peridotitic. The CL patterns and variation of δ13C values within diamonds indicate that at least two diamond growth events, interrupted by periods of resorption, occurred at Aviat. Nitrogen and δ13C are decoupled indicating that multiple fluid sources contributed to diamond formation at Aviat. Mantle residence temperatures for most Aviat diamonds range from ~1050-1150⁰C, indicating a range of source depths.
Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:AEU.10048/1966 |
Date | 11 1900 |
Creators | Peats, Jennifer |
Contributors | Stachel, Thomas (Earth and Atmospheric Sciences), Muehlenbachs, Karlis (Earth and Atmospheric Sciences, Currie, Claire (Physics) |
Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
Language | English |
Detected Language | English |
Type | Thesis |
Format | 179144407 bytes, application/pdf |
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