CGRG Bibliography of Canadian Geomorphology
Search Results
Author : Ferbey, T.; and Levson, V.M.
Date : 2001.
Title : Quaternary geology studies in the Huckleberry Mine area, Tahtsa Ranges, West-Central British Columbia.
Publication : Canadian Quaternary Association/ Association canadienne pour l'etude du Quaternaire, Annual Meeting 2001. Whitehorse, Yukon Territory, August 20 – 24, 2001.
Issue :
Page(s) :
Abstract
Detailed stratigraphic, sedimentologic, and geochemical studies were conducted in the area of Huckleberry Mine, a producing porphyry copper-molybdenum open pit mine in west-central BC. Complimentary glacial history and ice flow studies were conducted across five 1:50:000 NTS map sheets (93 E/10, 11, 14, 15, 16). Ice flow data indicate that glaciers in the early and late Fraser Glaciation, flowed easterly through the Huckleberry Mine area into the Nechako Plateau from high elevation areas in the Coast Mountains. However, west to southwest ice flow dominated in the region during the glacial maximum. The source of ice for this event was an ice dome east of the study area in central British Columbia. The dominant Quaternary unit found in the study area is a massive, matrix-supported diamict, up to 12 metres thick, interpreted as a basal till. It typically is clay-rich, overconsolidated, well jointed and fissile. Clasts are sub-angular to sub-rounded, commonly striated and often mineralized. Pyrite and chalcopyrite grains locally occur within the matrix. The till overlies glacially abraded bedrock, proximal glaciolacustrine sediments (laminated, stony silt and clay with interbedded sand and diamict lenses) or, less commonly, glaciofluvial gravels. Glacial units are typically capped, on steep valley slopes, by colluvial deposits and, in valley bottom settings, by thick peats. Nonglacial sediments under till in nearby areas have yielded radiocarbon dates in the 25-40 ka range and the till of the Huckleberry Mine area is therefore interpreted as being Late Wisconsinan in age. Geochemical analyses of basal tills, collected from surface exposures and Becker Hammer drill holes in the mine area, show significant variance in elemental concentrations, both laterally and vertically. Dispersal patterns are complex but copper concentrations in basal till (median: 226 ppm; maximum: 8924 ppm) generally decrease with increasing distance from known mineralization, as expected. However, although there are indications of both early and late easterly transport, a net westward dispersal is clearly observed in both surface and drill hole samples, even though the last ice-flow event was towards the east.
Bibliography of Canadian Geomorphology