CGRG Bibliography of Canadian Geomorphology
Search Results
Author : Ekes,C.; and Hickin, E.J.
Date : 2001.
Title : Ground penetrating radar facies of the paraglacial Cheekye Fan, southwestern British Columbia, Canada.
Publication : Sedimentary Geology
Issue : 143(3-4):
Page(s) : 199-217.
Abstract
Ground penetrating radar (GPR) surveys have been carried out in order to characterise reflection patterns and to assess the method's potential for imaging alluvial fan sediments in southwestern British Columbia, Canada. The results from Cheekye Fan show that GPR achieved over 40 m penetration with the 50 MHz antenna and provided data that allowed identification of 10 radar facies. Glacial till produces a reflection free configuration and bedrock radar facies is characterised by a hummocky pattern often with stacked macro-scale diffractions. Four subaerially deposited alluvial-fan facies were identified. Radar facies of the nearby meandering Squamish River are characterised by a complex, sigmoid oblique pattern that is clearly different from any configuration observed on Cheekye Fan. Based on the analysis of over 27 km radar data, the large-scale internal architecture of Cheekye Fan was reconstructed. Fan sediments are underlain by till and hummocky bedrock in the northern and eastern portion of the fan. Sedimentation was initiated by subaqueously deposited delta foresets following deglaciation of Upper Howe Sound. Subaerially deposited sediments can be divided into: (a) massive, matrix-rich diamicton that appears predominant at the core of the fan and at lower stratigraphic horizons, suggesting bouldery rock-slide or debris flow origin; and (b) horizontally-bedded sheetflood gravel dominating the upper 20¯25 m of the stratigraphic column.
Bibliography of Canadian Geomorphology