A spatial perspective on the New York drumlin field

This study spatially evaluates the applicability of a deformation approach to drumlin genesis for the New York drumlin field. It also assesses whether the Onondaga Escarpment, Appalachian Plateau, and Glacial Lake Iroquois influenced the spatial characteristics of drumlins. Spatial and morphometric analyses generally show a random drumlin distribution, down-ice increases in drumlin density, and down-ice decreases in drumlin elongation. These patterns are consistent with the deformation model. The Onondaga Escarpment, located transverse to ice flow, superimposed additional patterns. Compressive ice flow conditions near the escarpment: (1) nucleated drumlins through variable rates of clast deformation, drumlin densities thus increase and become clustered; and (2) reduced ice velocity so that drumlin streamlining was retarded. As the glacier advanced onto the Appalachian Plateau, drumlin-forming conditions declined because ice was nearly immobile on interfluves. Active ice was instead funneled into valleys now occupied by the Finger Lakes. Postformational erosion/burial of drumlins by Glacial Lake Iroquois removed drumlins in the northern portion of the field.