PATTERN RECOGNITION FROM INLAND DUNES USING TERRAIN ANALYSIS

Pattern analysis of dune fields from dune spacing and crest orientation has been seen as a potential source of information for dating of the dunes and determining the wind regimes which formed them. While these techniques have found application in active dune fields they have found less application to smaller, stabilized dune fields found across formerly glaciated terrain. Many of these inland dune fields have been dated to dry periods, particularly the Younger Dryas, occurring since the end of the last extensive glaciation of the continent and are mostly characterized by parabolic forms derived from progressive stabilization of fields. In particular, the mapping of dune fields used a GIS (Geographic Information System) based approach that implements digital elevation model (DEM) terrain analysis for characterization of terrain surfaces. The parameters that describe the terrain surfaces include derivatives such as slope, aspect, convergence indices, anisotropic coefficient values and other terrain surface parameters. We use exploratory data analysis (EDA) to evaluate morphometric characteristics of two dune fields in central Lower Michigan and systematically characterize the directional symmetry, or lack of symmetry, exhibited by the fields. In addition, the spatial patterns are evaluated through different measurements such as compactness and directional mean of the geographic distributions.