Indicator Mineral and Till Geochemical Dispersal Associated with the Ranch Lake Kimberlite, Lac de Gras Region, Northwest Territories

Book excerpt: The Ranch Lake kimberlite underlies Ranch Lake, located about 100 kilometres north-northwest of the Ekati diamond mine in the Lac de Gras area of the Northwest Territories. This report utilizes a combination of geological data sets to document the indicator mineral abundances in, and the chemistry of, the Ranch Lake kimberlite; document indicator mineral abundance patterns in till deposited down-ice from the kimberlite; document the till geochemical signature of the kimberlite down-ice; and estimate the effect of glacial abrasion with increasing distance down-ice by examining surface features & textures on pyrope garnet. Information is also included on the regional bedrock & surficial geology and sampling & analytical methods used. The results of this study will aid in the design of mineral exploration programs for kimberlite-hosted diamond deposits in glaciated terrain.