GLACIAL MORPHOSTRATIGRAPHIC INVESTIGATIONS IN CENTRAL NEW YORK STATE: NEW VIEWS ON OLD PROBLEMS

On-going mapping associated with the USGS STATEMAP program has afforded the opportunity to re-examine the classic glaciated landscape of central New York State. Using digital tools available through GIS, glacial researchers can take a new look at the Finger Lakes basins, through valleys, drumlin fields, moraine complexes and ice border drainage channels of a landscape that has long provided a rich morphostratigraphic record of glacial events. This newest look at the region is a consequence of geomorphic studies, analysis of sediment exposures, and a parallel bedrock geology study connected with 1:24,000 scale mapping of eight quadrangles in southern Onondaga County.

The results of this effort have defined surficial units, refined bedrock stratigraphy, and identified landforms. The data has been entered into a digital database, and the following GIS coverages generated: bedrock geology units, formation contact confidence, faults, dip direction, outcrop locations, surficial geology units, moraine ridges, ice border drainage channels, eskers, and drumlins. Attributes associated with these layers include age, thickness, lithology, and orientation. Layers for all eight quadrangles have been merged to form a complete coverage for the entire region. Additionally, a shaded relief, or hillshade, grid file was generated from 10m resolution DEM data. The hillshade product provides both an extraordinary new view of the glacial landscape of this region, and also allows the various surficial and bedrock geology layers to be directly draped on the hillshade image.

The GIS database constructed provides a dynamic viewing method where specific glacial landforms can be quickly referenced to the characteristics and spatial distribution of the underlying bedrock and/or surficial sediments. This approach to one of the classic regions studied by E. H. Muller has provided a new way to investigate the connections between glacial landforms, sediments, bedrock topography, and substrate lithology.