SPATIAL AND MORPHOLOGICAL ANALYSIS OF GLACIALLY ERODED LANDFORMS (P-FORMS) AT WHITEFISH FALLS, ONTARIO

Analysis of glacially eroded landforms and their spatial distribution can provide valuable information about past subglacial conditions. However, the precise mechanism of formation of many erosional landforms and the controls on their distribution are still poorly understood. Detailed morphological and spatial analysis of a suite of small-scale sculpted landforms known as p-forms eroded into Proterozoic bedrock of the Gowganda Formation near Whitefish Falls, Ontario, is presented here. These enigmatic erosional features show a variety of morphologies and sizes, and are sculpted into a range of bedrock types including quartzite, argillite, and diamictite. Investigation of the nature and spatial organization of these forms relative to local topography and former ice flow can provide valuable information regarding their mode of development.

The morphological characteristics and spatial distribution of p-forms exposed in a one square-kilometer area of bedrock slightly south of Whitefish Falls were documented. ProMark GPS data and ground-based measurements were used to document precise elevation, slope, and aspect measurements of different p-forms. Characteristics of the bedrock in which p-forms had developed were also recorded including the bedrock type, jointing patterns and fracture orientation. All data were input into GIS software and analysed using statistical regression techniques. Preliminary findings suggest a strong topographic control on the formation of p-forms in the Whitefish Falls area. Larger concentrations of forms are found on the up-glacier facing slopes of bedrock highs, although many similar forms are found on down-glacier facing slopes. Bedrock lithology also appears to have a strong influence on the type and level of development of p-forms with the most well-developed forms located on relatively easily eroded argillite. Additional analysis of these spatial data will focus on establishing the relationship between p-form type and the possible location of subglacial meltwater conduits. These field-based findings will also serve as a basis for correlations to theoretical models describing ice and fluid dynamics. It is hoped that further analysis of these data will contribute toward establishing a predictive model for p-form development.