USING GIS TO RE-EVALUATE LAKE VOLUMES USING SEISMIC REFLECTION PROFILES

Morphometric characteristics including area, depth, volume, and slope of the New York Finger Lakes originate from the classic work of Birge and Juday (1914). Lead-line sounding data used to determine morphometric characteristics was collected by successive classes (1878-1883) from the College of Civil Engineering, Cornell University, NY. To this date, researchers still use the original lake volumes as calculated by Birge and Juday (1914). What remains unknown is whether the original 405 lead-line soundings actually capture the heterogeneity of the Seneca Lake basin. Published seismic reflection profiles and bathymetry of Seneca Lake, NY from Mullins et al. (1996) were used to create a bathymetric model. This data combined with previously published lead-line data were used to digitize the bathymetric contour lines of the lake. These contours, including depth to bedrock and the depth to sediment, were imported into ArcGIS^TM. The volume of the sediment deposits was calculated by subtracting the two layers. A three-dimensional model of the bathymetry was constructed using ArcGIS Scene^TM. This resulted in a model of the Seneca Lake basin with and without sediment. Analysis of the model was conducted using ArcGIS^TM. Our results (27.98 km³) suggest the previously published calculations of lake volume (15.45 km³) by Birge and Juday (1914) do not fully capture the morphology of the lake basin.