A Descriptive Analysis of the Morphology of Prairie Mounds in Southern Alberta

Abstract

<p> Prairie mounds from the general area of Foremost-Cypress Hills, Alberta, have been described. Various morphometric parameters, including relative and absolute altitude of the mounds, depth of their central depressions, orientation of breaches in their rims, angle of the bounding slopes, and distribution of surficial stones were measured. Several characteristics of the mounds were found to be widespread. Firstly, the mounds occur in elongate fields that correspond roughly to the 3,000 ft. contour interval. Secondly, surficial stones invariably have their greatest concentration on the rims of the mounds. Also the mounds are frequently separated by interrupted drainage channels. The bounding slopes of the mounds are asymmetrical, with west and north-west slopes being least steep. Interpretation of these morphological observations and a consideration of the various hypotheses of formation proposed in the literature leads to the conclusion that prairie mounds most likely originated by the differential melting of a stagnant ice mass in a manner proposed by Gravenor in 1955, and have subsequently been modified by mass-wasting processes.