FACTORS INFLUENCING THE GRAIN OF THE TOPOGRAPHY ALONG THE WILLOUGHBY ARCH

Equal-area plots of maximum slope linears from each of three study areas along the Willoughby Arch in northeastern Vermont are analyzed and com- pared with the bedrock joint system and evidence of glacial ice movement within the respective areas. These analyses reveal a correspondence of the topographic fabric to the bedrock fracture pattern and a supplemen- tary relationship between the movement of glacial ice and the topography. This information indicates that the topography adjusted to the orientation of bedrock frac- tures before the Pleistocene. Chemical erosion is suggested as the major process effecting this relationship. The frac- ture-pattern-oriented topography prevails today with only slight modification by glaciation. This is confirmed by the linear data on the direction of glacial ice flow and the areal distribution of Pleistocene deposits on the three areas.