MULTIVARIATE MINERALOGICAL ANALYSIS OF SE DIMENTS FROM THE UPPER WISCONSINAN OF THE SOUTHWESTERN YUKON-TERRITORY

For this study, 84 samples of glacial and juxtaglacial sediments were collected in valleys of the Ruby Range and Aishihik Basin (southwester n Yukon). Analyses were conducted to quantify the heavy minerals in th e sand fraction and to assess the petrography of the gravel fraction. A cluster analysis performed on the heavy mineral results showed five groups of deposits, three of which are related to local glaciers insid e the Ruby Range, the other two being related to regional ice lobes of Kluane and Aishihik, respectively. The three groups of local sediment s correspond to the three lithologies of the Ruby Range, i.e., the gra nitic batholith, the schists, and the alaskite. The sediments from the regional ice lobes are characterized by highly diversified mineralogy and petrography and the relative abundance of minerals from the Saint Elias Mountains, the main source of the ice lobes. A correspondance f actor analysis performed on the heavy mineral results organizes sample s and minerals into a triangular cloud, the three vertices correspondi ng to biotite, carbonate, and titanite-garnet. These are the key eleme nts of local glaciers, Kluane ice lobe, and Aishihik ice lobe, respect ively. Finally, the study shows the extension of Kluane lobe in one va lley of the Ruby Range, the ice flow pattern in another valley, as wel l as a transfluence from Kluane lobe inside the Range.