Open File Report 2010-14

Open File Report 2010-14

OFR 2010-14

Till Geochemistry in the Sawn Lake Area, Southern Buffalo Head Hills, Alberta (NTS 84B/13)

Author(s) Prior, G.J. Date 2010-12-22

This report presents geochemical results for the <63 fraction="" of="" 67="" till="" samples="" and="" 1="" glaciofluvial="" sand="" sample="" from="" the="" sawn="" lake="" map="" area.="" fifty-four="" of="" the="" till="" samples="" and="" the="" glaciofluvial="" sample="" were="" collected="" in="" 2002.="" twelve="" till="" samples="" discussed="" in="" this="" report="" were="" collected="" before="" 2002="" and="" analyzed="" (reanalyzed)="" along="" with="" the="" 2002="" samples.="" kimberlite-indicator="" mineral="" (kim)="" data="" from="" these="" samples="" were="" released="">

Tills of the Sawn Lake area typically contain about 40% clay, 30% silt and 30% sand. Intriguing compositional differences exist between ablation till (ice-stagnation deposits) and non-ablation till (which includes basal till). On average, the ablation till has higher MgO, CaO, calcite and dolomite values, whereas the non-ablation till has higher Mo, U, Sb and Se values. These differences may reflect a higher component of Cretaceous shale, particularly organic-rich shale, in the basal till component of the non-ablation till compared to a somewhat greater amount of limestone and dolomite debris, derived from distant Paleozoic strata, in the ablation till.